***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 1 EO12866_GHG+Fuel Eff Stds for Med - Heavy - Duty Engines+Vehicles 2060 - AP61 FRM RIA_20110 722 _Ch 02 Technology and Cost Effectiveness .docx 

## Chapter 2: **Te chnologies, Cost, and Effectiveness**  **2.1 Overview of**  **Technologies** In discussing the potential for CO 2 emission and fuel consumption reductions, it can be helpful to think of the work flow through the s ys tem. The initial work input is fuel. Each gallon of fuel has the potential to produce some amount of work and will produce a set amount of CO 2 (about 22 pounds (10 kg) of CO 2 per gallon of diesel fuel). The engine converts the chemical energy in the fuel to useable work to move the truck. Any reductions in work demanded of the engine b y the vehicle or improvements in engine fuel conversion efficiency will lead directly

to CO 2 emission and fuel consumption reductions. Current diesel engines are 35 - 38 percent efficient over a range of operating conditions with peak efficiency

levels between 40 and 45 percent depending on engine sizes and applications, while gasoline engines are approximately 30 percent efficient overall. This means that approximately one - third of the fuel’s chemical energy is converted to useful work and two - thirds is lost to friction, gas e xchange, and waste heat in the coolant and exhaust. In turn, the truck uses this work delivered b y the engine to overcome overall vehicle - related losses such as aerodynamic drag, tire rolling resistance, friction in the vehicle driveline, and to provide a uxiliary power for components such as air conditioning and lights. L astl y, the vehicle’s operation, such as vehicle speed and idle time, affects the amount of total energy required to complete its activity . While it may be intuitive to look first to the engine for CO 2 reductions given that only about one - third of the fuel is converted to useable work, it is important to realize that any improvement in vehicle efficiency reduces both the work demanded and also the waste energy in proportion. Technology

i s one pathway

to improve heavy - duty

truck GHG emissions and fuel consumption . Near - term solutions exist, such as those being deployed b y SmartWay partners in heav y - dut y truck long haul applications. Other solutions are currently underway

in the Li ght - Dut y vehicle segment, especiall y in the Large Pickup sector where many of the technologies can apply

to the heav y - dut y pickup trucks covered under this rulemaking . Long term solutions are currently under development to improve efficiencies and cost - effective ness. While there is not a “silver bullet” that will significantly eliminate GHG emissions from heav y - dut y trucks like the catal yt ic converter has for criteria pollutant emissions, significant GHG and fuel consumption reductions can be achieved through a c ombination of engine, vehicle s ys tem, and operational technologies. The following sections will discuss technologies in relation to each of the regulatory categories

– Heav y - D ut y Pickup Trucks and Vans, Heav y - D uty Engines, Class 7/8 Sleeper**Regulatory Impact Anal ysis** 

2 - 2

and Day Cabs, and Class 2b - 8 Vocational Vehicles . Ineach of these sections information on technological approaches, costs, and percent improvements is provided. Not all of the technologies discussed in these sections are assumed to be used for compliance with the eng ine and vehicle standards, for reasons that are also discussed in each section. A summary of technologies, costs, fuel consumption and GHG emissions improvement percentages is provided in Tables 2 - 36 and 2 - 37 at the end of this chapter for each of the eng ine/vehicle ty pes listed above. EPA and NHTSA collected information on the cost and effectiveness of fuel consumption and CO 2 emission reducing technologies from several sources. The primary sources of information were the 2010 National Academ y of Science s report o n Technologies and Approaches to Reducing the Fuel Consumption of Medium - and Heavy - Duty Vehicles (NAS) 1 , TIAX’s assessment of technologies to support the NAS panel report (TIAX) 2 , EPA’s Heav y - D uty Lumped Parameter Model 3 , the anal ys is conducted by NESCCAF, ICCT, Southwest Research Institute and TIAX for reducing fuel consumption of heav y - dut y long haul combination tractors (NESCCAF/I CCT) 4 , and the technology cost anal ysis conducted b y IC F for EPA (I CF). 5 In addition, the agencies used the vehicle simulation model (the Greenhouse Gas Emissions Model or GEM) to quantify the effectiveness of various technolog ies on CO 2 emission and fuel consumption reductions in terms of vehicle performance as they

are evaluated in determining compliance with the HD program . The simulation tool is described in RIA Chapter 4 in more detail . 

### 2.1.1 **Baseline Engine and Vehicle Configuration** The agencies have derived the baseline engine and vehicle configuration fo r each regulatory

category by

examining engines and vehicles in the existing fleet to represent the ty pical 2010 model ye ar vehicle and engine , as described later in this RIA chapter . The technology

paths that the agencies considered available for each category for purposes of determining what regulatory standards would be cost - effective, and technologically feasible and otherwise appropriate in the leadtime afforded by the rule are, in turn, built from the baseline. **Table 2**  **- 1**  **: Baseline Engine and Vehicle Configurations** Regulatory Category Baseline Configuration Heavy - Duty Gasoline Pickup Truck and Van  V8 engine  Electronic control  N aturally aspirated  Coupled cam phasing  6 speed automatic transmission Heavy - Duty Diesel Pickup Truck and Van  2010 emission compliant diesel engine  Electronic control  6 speed automatic transmission Heavy - Duty Gasoline Engine  V8 engine  Electronic control  N aturally aspirated***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 3  F ixed valve timing Heavy - Duty Diesel Engine  Electronic control  SCR/EGR/DPF exhaust aftertreatment system which achieves 2010MY criteria emissions standards  Turbocharged with v ariable geometry turbocharger  2200 bar injection pressure  Single fixed overhead valve  Belt driven accessories Combination Tractor  Aerodynamics: tractor fleet consists of 25% Bin I , 70% Bin II , and 5% Bin III  Tires: Dual tires with steel wheels, RRc=7.8 (steer) and 8.2 (drive)  Body and Chassis: steel components  Idle Reduction: Currently 30% of sleeper cabs contain an idle reduction technology, but not necessarily an automatic engine shutoff  Vehicle Speed Limiter: 0% of tractors contain a non - override VSL set at below 65 mph Vocational Vehicle  Tires: average tire with a RRc=9.0 

### 2.2 **Overview of Technology Cost Methodology** Section 2.2.1 presents the methods used to address indirect costs in this analysis. Section 2.2.2 p resents the learning effects applied throughout this analy sis. Section 2.9 presents a summary in tabular form of all the technology costs expected to be implemented in response to the standards. 

### 2.2.1 **Markups to Address Indirect Costs** To produce a unit of output, e ngine and truck manufacturers incur direct and indirect costs. Direct costs include cost of materials and labor costs. Indirect costs are all the costs associated with producing the unit of output that are not direct costs

– for example, they may be related to production (such as research and development [R&D]), corporate operations (such as salaries, pensions, and health care costs for corporate staff), or selling (such as transportation, dealer support, and marketing). Indirect costs are generall y recovered b y allocating a share of the costs to each unit of good sold . Although it is possible to account for direct costs allocated to each unit of good sold, it is more challenging to account for indirect costs allocated to a unit of goods sold. To make a cost anal ys is process more feasible, markup factors, which relate total indirect costs to total direct costs, have been developed. These factors are often referred to as retail price equivalent (RPE) multipliers.**Regulatory Impact Anal ysis** 

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Cost ana ly sts and regulatory agencies ( including both EPA and NHTSA) have frequentl y used these multipliers to predict the resultant impact on costs associated with manufacturers’ responses to regulatory requirem ents. T he best approach , if it were possible, to determining the impact of changes in direct manufacturing costs on a manufacturer’s indirect costs would be to actually estimate the cost impact on each indirect cost element. However, doing this within the constraints of an agency ’s time or budget is not alway s feasible, or the technical, financial, and accounting information to carry out such an analysis may simply be unavailable. RPE multipliers provide, at an aggregate level, the relative shares of revenues ( Revenue = Direct Costs + Indir ect Costs + Net Income ) to direct manufacturing costs. Using RPE multipliers implicitly assumes that incremental changes in direct manufacturing costs produce common incremental changes in all indirect cost contributors as well as net income. However, a concern in using the RPE multiplier in cost anal ys is for new technologies added in response to regulatory

requirements is that the indirect costs of vehicle modifications are not likely to be the same for different technologies. For example, less complex technologies could require fewer R&D efforts or less warranty coverage than more complex technologies. In addition, some simple technological adjustments may , for example, have no effect on the number of corporate personnel and the indirect costs attributable to those personnel . The use of RPEs, with their assumption that all technologies have the same proportion of indirect costs, is likely

to overestimate the costs of less complex technologies and underestimate the costs of more complex technologies. T o address this concern, modified multipliers have been developed by EPA, working with a contractor, for use in rulemakings . These multipliers are referred to as indirect cost multipliers (or IC Ms ). Incontrast to RPE multipliers, ICMs assign unique incre mental changes to each indirect cost contributor as well as net income.

ICM = (direct cost + adjusted indirect cost)/(direct cost) Developing the ICMs from the RPE multipliers requires developing adjustment factors based on the complexity

of the technology

and the time frame under consideration : the less complex a technology , the lower its ICM, and the longer the time frame for applying the technology , the lower the I CM . Th is methodology w as used in the cost estimation for the recent l ight - d

ut y fuel economy

and GHG rule. The I CMs for the light - duty context were developed in a peer - reviewed report from RTI International and were subsequently discussed in a peer - reviewed journal article. 6 For the heav y - dut y pickup truck and van cost projecti ons in the proposal, the agencies used I CM adjustment factors developed for light - duty vehicles , inclusive of a return on capital , primaril y because the manufacturers involved in this segment of the heav y - dut y market are the same manufacturers which build light - dut y trucks. The cost of capital (reflected in profit) is included because of the assumption implicit in I CMs (and RPEs) that capital costs are proportional to direct costs, and businesses need to be able to earn returns on their investments. The capital costs are those associated with the incremental costs of the new technologies.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 5 For th e combination tractor s , vocational vehi cles , and heav y - dut y engine cost projections in the proposal , EPA contracted with RTIInternational to update EPA’s methodology

for accounting for indirect costs associated with changes in direct manufacturing costs for heav y - dut y engine and truck manufacturers. 7 In addition to the indirect cost contributors varying by

complexity

and time frame, there is no reason to expect that the contributors would be the same for engine manufacturers as for truck manufacturers. The resulting report from RTI provides a description of the methodology , as well as calculations of the indirect cost multipliers used in the proposal . These indirect cost multipliers were used, along with calculations of direct manufacturing costs, to provide estimates of the full additional costs associated with new technologies. For the anal ys is supporting this final rulemaking, the agencies have made some changes to both the ICMs factors and to the method of appl yi ng those factors to arrive at a final cost estimate. The first of these changes was done in response to continued thinking among the EPA -NHTSA team about how past ICMs have been developed and what are the most appropriate data sources to rel y upon in determining the appropriate ICMs. The second c hange has been done in response to both staff concerns and public feedback suggesting that the agenc ies were inappropriately appl yi ng learning effects to indirect costs via the multiplicative approach to applying the ICMs. Regarding the first chan ge – to the I CM factors themselves

– a little background must first be provided. In the original work done under contract to EPA b y RTI International, 8 EPA experts had undergone a consensus approach to determining the impact of specific technology

changes on the indirect costs of a company . Subsequent to that effort, EPA experts underwent a blind survey to make this determination on a different set of technology changes. This subsequent effort, referred to b y EP A as a modified - Delphi approach, resulted i n different ICM determinations. This effort is detailed in a memorandum contained in the docket for this rule. 9 Upon completing this effort, EPA determined that the original RTI values should be averaged with the modified - Delp hi values to arrive at the final I CMs for low and medium complexity

technologies and that the original RTI values would be used for high complexity

level 1 while the modified - Delphi values would be used for high complexity level 2 . These final ICMs were u sed in the 2012 - 2016 light - dut y GHG/CAFE rulemaking. Subsequent to that, EPA contracted RTI to update their light - dut y report with an eye to the heav y - dut y industry . In that effort, RTI determined the RPE of both the heavy - duty engine and heav y truck ind

ustries, then applied the light - duty indirect cost factors

—those resulting from the averaging of the values from their original report with the modified - Delphi values

— to the heav y - dut y RPEs to arrive at heav y - dut y specific ICMs. That effort is described i n their final heav y - duty

I CM report mentioned above. 10 More recentl y, the EPA and NHTSA team has decided that the original light - duty RTI values, given the technologies considered for low and medium complexity , should no longer be used and that we should re ly solel y on the modified - Delphi values for these complexity levels. The original light - duty RTI study

used low rolling resistance tires as a low complexity technology

example and a dual clutch transmission as a medium complexity technology . Upon further thought, the technologies considered for the modified Delphi values (passive**Regulatory Impact Anal ysis** 

2 - 6

aerodynamic improvements for low complexity and turbocharging with do wnsizing for medium complexity

_ were considered to better represent the example technologies ) . As a result, the modified - Delphi values were to become the working ICMs for low and medium complexity rather than averaging those values with the original RTI report values. NHTSA and EPA staff also re - examined the technology complexity

categories that we re assigned to each light - dut y technology and modified these assignments to better reflect the technologies that are now used as proxies for each category . This decision impacts the low and medium complexity heavy - dut y ICMs too because the modified - Delphi values alone were now to be applied to the heav y - dut y RPEs to arrive at heav y - duty I CMs rather than using the averaged values developed for the 2012 - 2016 rule. A secondary - level change was also made as part of this I CM recalculation to the light duty I C Ms and, therefore, to the I CMs used in this anal ys is for HD pickups and vans. That change was to revise upward the RPE level reported in the original RTI report from an original value of 1.46 to 1.5 to reflect the long term average RPE. The original RTIstudy was based on 2008 data. However, an anal ys is of historical RPE data indicates that, although there is year to year variation, the average RPE has remained roughl y 1.5. ICMs will be applied to future ye ar’s data and therefore NHTSA an d EPA staff believe that it would be appropriate to base ICMs on the historical average rather than a single year’s result. Therefore, ICMs were adjusted to reflect this average level. . As a result, the Hi gh 1 and High 2 I CMs used for HD pickups and vans have also changed. Table 2 - 2 shows both the I CM values used in the proposal and the new ICM values used for the anal ys is supporting this final rule . Near term values (2014 through 2021 in this anal ys is ) account for diff erences in the levels of R&D, tooling, and other indirect costs that will be incurred. Once the program has been fully implemented, some of the indirect costs will no longer be attributable to the standards and, as such, a lower ICM factor is applied to d irect costs in 2022 and later.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 7 **Table 2**  **- 2**  **Indirect Cost Multipliers Used in this Analysis a**  PROPOSAL FINAL CLASS COMPLEXITY NEAR TERM LONG

TERM NEAR

TERM LONG

TERM HD Pickup Trucks and Vans Low 1.17 1.13 1.24 1.19 Medium 1.31 1.19 1.39 1.29 High1 1.51 1.32 1.56 1.35 High2 1.70 1.45 1.77 1.50 Loose diesel engines Low 1.11 1.09 1.15 1.12 Medium 1.18 1.13 1.24 1.18 High1 1.28 1.19 1.28 1.19 High2 1.43 1.29 1.43 1.29 Loose gasoline engines Low 1.17 1.13 1.24 1.19 Medium 1.31 1.19 1.39 1.29 High1 1.51 1.32 1.56 1.35 High2 1.70 1.45 1.77 1.50 Vocational Vehicles and Combination Tractors Low 1.14 1.10 1.18 1.14 Medium 1.26 1.16 1.30 1.23 High1 1.42 1.27 1.42 1.27 High2 1.57 1.36 1.57 1.36 a Rogozhin, A., et. al., “Using indirect cost multipliers to estimate the total cost of adding ne w technology in the automobile industry,” International Journal of Production Economics (2009) ; “Documentation of the Development of Indirect Cost Multipliers for Three Automotive Technologies,” Helfand, G., and Sherwood, T., Memorandum dated August 2009; “ Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers ,” Draft Report prepared by RTI International and Transportation Research Institute, University of Michigan, July 2010 The second change made to the I CMs has to do with the way in which the ICMs are applied. To date, we have applied the ICMs, as done in an y anal ys is that relied on RPEs, as a pure multiplicative factor. This way , a direct manufacturing cost of, say , $1 0 0 would be multiplied by

an ICM of 1.24 to arrive at a marked up technology cost of $124. However, as learning effects (discussed below) are applied to the direct manufacturing cost, the indirect costs are also reduced accordingl y. Therefore, in year 2 the $100 direct manufacturing cost might reduce to $97 and the marked up cost would become $120 ($97 x 1.24). As a result, indirect costs have been reduced from $24 to $20. Given that indirect costs cover man y things such as facility - related costs, electricity , etc., it is perhaps not appropriate to appl y the ICM to the learned direct costs, at least not for those indirect cost elements unlikely to change with learning. The EPA - NHTSA team believes that it is appropriate onl y to allow warrant y costs to decrease with learning since warranty costs are tied to direct manufacturing costs (since warrant y t ypically involves replacement of actual parts whic h should be less costly with learning). However, the remaining elements of the indirect costs should remain constant ye ar - over - ye ar, at least until some of those indirect costs are no longer attributable to the rulemaking effort that imposed them (such as R&D).**Regulatory Impact Anal ysis** 

2 - 8

As a result, the ICM calculation has become more complex with the analy sis supporting this final action. We must first establish the year in which the direct manufacturing costs are considered “valid.” For example, a cost estimate might be conside red valid today , or perhaps not until high volume production is reached which will not occur until MY 2015. That year is known as the base ye ar for the estimated cost. That cost is the cost used to determine the “non - warrant y” portion of the indirect cos ts. For example, the non warranty portion of the loose diesel engine low complexity I CM in the short - term is 0.1 49 (the warrant y versus non - warrant y portions of the ICMs are shown in Table 2 - 3 ). For the improved water pump technology we have estimated a direct manufacturing cost of $ 7 9 in MY 2014. So the non - warrant y portion of the indirect costs would be $11. 77 ($79 x 0.1 49 ). This value would be added to the lear ned direct manufacturing cost for each year through 2021. Beginning in 2022, when long - term indirect costs begin, the additive factor would become $9. 64 ($79 x 0.12 2 ). Additionally , the $79 cost in 2014 would become $76.63 in MY 2015 due to learning ($79 x (1 - 3%)). So, while the warrant y portion of the indirect costs would be $0. 47 ($79 x 0.0 06 ) in 2014, they would decrease to $0. 46 ($76 x 0.0 06 ) in 2015 as warranty costs decrease with learning. The resultant indirect costs for the water pump would be $12. 2 4 ($11. 77 +$0. 47 ) in MY 2014 and $12. 23 ($11. 77 +$0. 4 6) in MY2015, and so on for subsequent years. **Table 2**  **- 3**  **Warranty and Non -**  **Warranty Portions of ICMs** SH ORT - TERM LONG - TERM CLASS COMPLEXITY WARRANTY NON WARRANTY WARRANTY NON WARRANTY HD Pickup Trucks and Vans Low 0.012 0.230 0.005 0.187

Medium 0.045 0.343 0.031 0.259 High1 0.065 0.499 0.032 0.314 High2 0.074 0.696 0.049 0.448 Loose diesel engines Low 0.006 0.149 0.003 0.122

Medium 0.022 0.213 0.016 0.165 High1 0.032 0.249 0.016 0.176 High2 0.037 0.398 0.025 0.265 Loose gasoline engines Low 0.012 0.230 0.005 0.187

Medium 0.045 0.343 0.031 0.259 High1 0.065 0.499 0.032 0.314 High2 0.074 0.696 0.049 0.448 Vocational Vehicles and Combination Tractors Low 0.013 0.165 0.006 0.134

Medium 0.051 0.252 0.035 0.190 High1 0.073 0.352 0.037 0.233 High2 0.084 0.486 0.056 0.312***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 9 There is some level of uncertainty surrounding both the I CM and RPE markup factors. The ICM estimates used in this final rulemaking group all technologies into three broad categories and treat them as if individual technologies within each of the three c ategories (low, medium, and high complexity ) will have the same ratio of indirect costs to direct costs. This simplification means it is likely that the direct cost for some technologies within a category

will be higher and some lower than the estimate fo r the category in general. More importantly , the IC M estim ates have not been validated through a direct accounting of actual indirect costs for individual technologies. Rather, the ICM estimates were developed using adjustment factors developed in two separate occasions: the first, a consensus process, was reported in the RTI report; the second, a modified Delphi method, was conducted separately and reported in an EPA memo. Both these panels were composed of EPA staff members with previous background in the automobile industry ; the memberships of the two panels overlapped but were not the same. The panels evaluated each element of the industry ’s RPE estimates and estimated the degree to which those elements would be expected to change in proportion to ch anges in direct manufacturing costs. The method and estimates in the RTI report were peer reviewed by three industry

experts and subsequently by reviewers for the International Journal of Production Economics. 11 RPEs themselves are inherently difficult to estimate because the accounting statements of manufacturers do not neatl y categorize all cost elements as either direct or indirect costs. Hence, each researcher developing an RPE estimate must apply

a certain amount of judgment to the allocation of the costs. Moreover, RPEs for heav y - and medium - duty trucks and for engine manufacturers are not as well studied as they

are for the light - dut y automobile industry . Since empirical estimates of I CMs are ultimatel y derived from the same data used to measure RPEs, this affects both measures. However, the value of RPE has not been measured for specific technologies, or for groups of specific technologies. Thus , even if we assume that the examined technology accuratel y represents the average impact on all techn ologies in its representative category , appl yi ng a single average RPE to any given technology by definition overstates costs for very simple technologies, or understates them for more advanced technologies in that group . 

### 2.2.2 **Learning Effects on Technology Co sts**  For some of the technologies considered in this analy sis, manufacturer learning effects would be expected to play a role in the actual end costs. The “learning curve” or “experience curve” describes the reduction in unit production costs as a function of accumulated production volume. In theory , the cost behavior it describes applies to cumulative production volume measured at the level of an individual manufacturer, although it is often assumed

— as both agencies have done in past regulatory analy ses —t o apply

at the industry - wide level, particularl y in industries that utilize many common technologies and component supply sources. Both agencies believe there are indeed many factors that cause costs to decrease over time. Research in the costs of manuf acturing has consistently

shown that, as manufacturers gain experience in production, they are able to appl y innovations to simplify machining and assembl y operations, use lower cost materials, and reduce the number or complexity

of component parts. All o f these factors allow manufacturers to lower the per - unit cost of production (i.e., the manufacturing learning curve). 12**Regulatory Impact Anal ysis** 

2 - 10

NHTSA and EPA have a detailed description of the learning effect in the 2012 - 2016 light - duty rule. Most studies of the effect of experience or learning on production costs appear to assume that cost reductions begin only after some initial volume threshold has been reached, but not all of these studies specify this threshold volume. The rate at which costs decline beyond the initial thr eshold is usually expressed as the percent reduction in average unit cost that results from each successive doubling of cumulative production volume, sometimes referred to as the learning rate. Man y estimates of experience curves do not specify a cumulati ve production volume beyond which cost reductions would no longer occur, instead depending on the asy mptotic behavior of the effect for learning rates below 100 percent to establish a floor on costs. In past rulemaking analyses, as noted above, both agen cies have used a learning curve algorithm that applied a learning factor of 20 percent for each doubling of production volume. NHTSA has used this approach in analy ses supporting recent CAFE rules. In its analy sis, EPA has simplified the approach b y usi ng an “every two years” based learning progression rather than a pure production volume progression (i.e., after two years of production it was assumed that production volumes would have doubled and, therefore, costs would be reduced by 20 percent). In the 2012 - 2016 light - duty rule, the agencies employed an additional learning algorithm to reflect the volume - based learning cost reductions that occur further along on the learning curve. This additional learning algorithm was termed “time - based” learning simply as a means of distinguishing this algorithm from the volume - based algorithm mentioned above, although both of the algorithms reflect the volume - based learning curve supported in the literature. 13 To avoid confusion, we are now referring to this learning algorithm as the “flat - portion” of the learning curve. This way , we maintain the clarit y that all learning is, in fact, volume - based learning , the level of cost reductions depend only on where on the learning curve a technology ’s learning progres sion is. We distinguish the flat - portion of the curve from the steep - portion of the curve to indicate the level of learning taking place in the ye ars following implementation of the technology . The agencies have applied the steep - portion learning algorithm for those technologies considered to be newer technologies likel y to experience rapid cost reductions through manufacturer learning and the flat - portion learning algorithm for those technologies considered to be mature technologies likely to experience minor cost reductions through manufacturer learning. As noted above, the steep - portion learning algorithm result s in 20 percent lower costs after two full ye ars o f implementation (i.e., the 2016 MY costs are 20 percent lower than the 201 4 and 201 5 model year costs). Once two steep - portion learning steps have occurred (for technologies having the steep portion learning algorithm applied while flat - portion learning would begin in year 2 for technologies having the flat - portion learning algorithm applied) , f lat - portion learning at 3 percent per ye ar becomes effective for 5 ye ars. Beyond 5 years of learning at 3 percent per ye ar, 5 years of learning at 2 percent per year, then 5 at 1 percent per ye ar become effective. Learning effects are applied to mos t but not all technologies because some of the expected technologies are already used rather widely

in the industry

and, presumabl y, learning impacts have already occurred. The steep - portion learning algorithm was applied for only a handful of technologie s that are considered to be new or emerging technologies. Most technologies have been considered to be more established given their current use in the fleet***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 11 and, hence, the lower flat - portion learning algorithm has been applied. The learning algorithms a

pplied to each technol ogy are summarized in Table 2 - 4 .**Regulatory Impact Anal ysis** 

2 - 12 **Table 2**  **- 4**  **Learning Effect Algorithm**  **s Applied to Technologies Used in this Analysis** TECHNOLOGY APPLIED TO LEARN ING ALGORITHM Cylinder head improvements Engines Flat Turbo efficiency

improvements Engines Flat EGR cooler efficiency

improvements Engines Flat Water pump improvements Engines Flat Oil pump improvements Engines Flat Fuel pump improvements Engines Flat Fuel rail improvements Engines Flat Fuel injector improvements Engines Flat Piston improvements Engines Flat Valve train friction reductions Engines Flat Turbo compounding Engines Flat Engine friction reduction Engines Flat Coupled cam phasing Engines Flat Stoichiometric gasoline direct injection Engines Flat Low rolling resistance tires Vocational vehicles Flat Low rolling resistance tires Trucks Flat Aero (except Aero SmartWay Advanced) Trucks Flat Aero SmartWay

Advanced Trucks Steep Weight reduction (via single wide tires and/or aluminum wheels) Trucks Flat Auxiliary power unit Trucks Flat Air conditioning leakage Trucks Flat The learning effects discussed here impact the technology costs considered here in that those technology

costs for which learning effects are considered applicable are changing throughout the period of implementation and the period following implementation. For example, some of the technology costs considered in this analy sis are taken from the 20 12 - 2016 light - duty

rule and scaled appropriatel y giving consideration to the heavier weights and loads in the heav y - dut y s egment. Man y of the costs in the 2012 - 2016 light - duty rule were consider “ applicable ” for the 2012 model year. If flat - portion learning were applied to those technologies, the 2013 cost would be 3 percent lower than the 2012 cost, and the 2014 model ye ar cost 3 percent lower than the 2013 cost, etc. As a result, the 2014 model y ear cost presented in, for example, Section 2.3 would reflect those two years of flat learning and would not be identical to the 2012 model year cost presented in the 2012 - 2016 light - duty rule. 

### 2.3 **Heavy -**  **D uty**  **Pickup Tru ck**  **and Van (Class 2b**  **and 3) Technologies and**  **Costs 2.3.1**  **Gasoline Engines** Spark ignited (gasoline) engines used in Class 2b and 3 vehicles include engines offered in a manufacturer’s light - dut y truck counterpart s, as well as engines specific to the***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 13 Class 2b and 3 segment. Based on 2010 MY specifications, these engines ty pically range in displacement between 5 and 7 liters , though smaller and larger engines have also been used in this market. The majority of these engines are a V8 configuration , although the V10 configuration is also marketed . The engine technologies are based on the technologies described in the Light - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards Joint Technical Support Document. 14 Some of the reference s come from the 2010 NAS Report, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heav y - D ut y Vehicles . These technologies include engine friction reduction, cam phasing, cylinder deactivation and stoichiometric gas direct injection. In cluded with each technology

description is an estimate of the improvement in fuel consumption and GHGs that is achievable through the use of the technology in heavy - dut y pickup trucks and vans. Table 2 - 37 at the end of this chapter shows the total potential improvement in heavy - dut y pickup and van fuel consumption and GHG emissions that can be achieved with the use of technologies described in this section. 2.3.1.1 **Low Friction Lubricants** One of the most basic methods of reducing fuel consumption in both gasoline and diesel engines is the use of lower viscosit y engine lubricants. More advanced multi - viscosity engine oils are available today with impro ved performance in a wider temperature band and with better lubricating properties. This can be accomplished by changes to the oil base stock (e.g., switching engine lubricants from a Group I base oils to lower - friction, lower viscosity Group III s yntheti c) and through changes to lubricant additive packages (e.g., friction modifiers and viscosity

improvers). The use of 5W - 30 motor oil is now widespread and auto manufacturers are introducing the use of even lower viscosity oils, such as 5W - 20 and 0W - 20, to improve cold - flow properties and reduce cold start friction. However, in some cases, changes to the crankshaft, rod and main bearings and changes to the mechanical tolerances of engine components may

be required. In all cases, durability testing would b e required to ensure that durability

is not compromised. The shift to lower viscosity and lower friction lubricants will also improve the effectiveness of valvetrain technologies such as cylinder deactivation, which rel y on a minimum oil temperature (visc osit y) for operation. Based on 2012 - 2016 Light - duty final rule, and previously - received confidential manufacturer data, NHTSA and EPA estimated the effectiveness of low friction lubricants to be between 0 to 1 percent. In the 2012 - 2016 light - duty FRM, the agencies estimated the cost of moving to low friction lubricants at $3 per vehicle (2007$). That estimate included a markup of 1.11 for a low complexity

technology . For C lass 2b and 3, we are using the same base estimate but have marked it up to 200 9 dol lars using the GDP price deflator and have used a markup of 1. 24 for a low complexity

technology

to arrive at a value of $4 per vehicle. As in the light - dut y rule, learning effects are not applied to costs for this technology and, as such, this estimate a pplies to all model years. 15 , 16**Regulatory Impact Anal ysis** 

2 - 14

2.3.1.2 **Engine Friction Reduction** Manufacturers can reduce friction and improve fuel consumption by improving the design of engine components and subsy stems. Approximately 10 percent of the energy consumed b y a vehicle is lost to friction, and just over half is due to frictional losses within the engine. Examples include improvements in low - tension piston rings, piston skirt design, roller cam followers, improved crankshaft design and bearings, material coatings, material substitutio n, more optimal thermal management, and piston and cylinder surface treatments. Additionally , as computer - aided modeling software continues to improve, more opportunities for evolutionary

friction reductions may

become available. All reciprocating and rot ating components in the engine are potential candidates for friction reduction, and minute improvements in several components can add up to a measurable fuel economy improvement. The 2012 - 2016 LD rule, 2010 NAS, NESCCAF and EEA reports as well as confidential manufacturer data suggested a range of effectiveness for engine friction reduction to be between 1 to 3 percent. NHTSA and EPA continue to believe that this range is accurate. Consistent with the 2012 - 2016 light - dut y FRM, the agencies estimate the co st of this technology

at $ 15 per cylinder compliance cost ( 200 9 $), including the low complexity I CM markup value of 1. 24 . Learning impacts are not applied to the costs of this technology and, as such, this estimate applies to all model years. This cost is multiplied by the number of engine cylinders. 2.3.1.3 **Variable Valve Timing** Variable valve timing (VVT) classifies a famil y of valve - train designs that alter the timing of the intake valve, exhaust valve, or both, primarily to reduce pumping losses, increase spec ific power, and control the level of residual gases in the cylinder. VVT reduces pumping losses when the engine is lightly loaded by

controlling valve timing closer to the optimum needed to sustain horsepower and torque. VVT can also improve volumetric e fficiency at higher engine speeds and loads. Additionally , VVT can be used to alter (and optimize) the effective compression ratio where it is advantageous for certain engine operating modes ( e.g. , in the Atkinson Cycle). VVT has now become a widely adopt ed technology in the light duty fleet : in MY 2007, over half of all new cars and light trucks had engines with some method of variable valve timing. 17 Manufacturers are currentl y using many different types of variable valve timing, which have a variety of different names and methods. Therefore, the degree of further improvement across the fleet is limited by the level of valvetrain technology already implemented on the vehicles. The three major t yp es of VVT are listed below. Each of the implementations of VVT uses a cam phaser to adjust the camshaft angular position relative to the crankshaft position, referred to as “camshaft phasing.” The phase adjustment results in changes to the pumping work required b y the engine to accomplish the gas exchange process . The majority of current cam phaser applications use hydraulicall y -***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 15 actuated units, powered by engine oil pressure and managed by a solenoid that controls the oil pressure supplied to the phaser. Based on a survey of the current powertrains being applied to the Class 2b and 3 segment and the level of powertrain sharing with the light duty vehicle market for these vehicles, the majorit y of light heav y dut y gasoline engines in the 2010 Class 2b and 3 vehicle models are utilizing some form of cam phasing to achieve power and emission goals , and so this technology

is considered to be in the baseline . **2.3.1.3.1 Coupled Cam Phasing**  **for Overhead Valve (OHV) and Single Overhead**

**Camshaft (SOHC) Engines** Valvetrains with coupled (or coordinated) cam phasing (CCP) can modify th e timing of both the inlet valves and the exhaust valves an equal amount by varying the phasing of the camshaft across an engine’s range of operating speeds; also known as variable valve timing (VVT). For engines configured as an overhead valve (OHV) or a s a single overhead camshaft (SOHC) only

one cam phaser is required per camshaft to achieve CCP Consistent with the 2012 - 2016 light - dut y rule, the agencies continue to agree with the effectiveness values of 1 to 4 percent reduction in fuel consumption fo r this technology . **2.3.1.3.2 Intake Cam Phasing (ICP) for Dual Overhead Camshaft Engines (DOHC)**  Valvetrains with ICP, which is the simplest of the cam phasing technologies, can modify the timing of the inlet valves by phasing the intake camshaft while the exhaust va lve timing remains fixed. This requires the addition of a cam phaser on each bank of intake valves on the engine. An in - line 4 - cylinder engine has one bank of intake valves, while V configured engines have two banks of intake valves. Some newer Class 2b and 3 market entries are offering dual overhead camshaft (DOHC) engine designs where two camshafts are used to operated the intake and exhaust valves independentl y. Currentl y, for Class 2b and 3 segment , onl y intake camshaft phasing (I CP) technology

is app lied. Consistent with the 2012 - 2016 light - dut y rule, the agencies continue to agree with the effectiveness values of 1 to 2 percent reduction in fuel consumption for this technology . **2.3.1.3.3 Dual Cam Phasing (DCP)**  **for Dual Overhead Camshaft Engines (DOHC)** The most flexible VVT design is dual (independent) cam phasing, where the intake and exhaust valve opening and closing events are controlled independentl y. This option allows the option of controlling valve overlap, which can be used as an internal EGR strategy. At low engine loads, DCP creates a reduction in pumping losses, resulting in improved fuel consumption. Increased internal EGR also results in lower engine - out NO X emissions. The amount by

which fuel consumption is improved depends on the residual tolerance of the combustion sy stem. Additional improvements are observed at idle, where low valve overlap**Regulatory Impact Anal ysis** 

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could result in improved combustion stability , potentially reducing idle fuel consumption. DCP requires two cam phaser s on each bank of the engine. Using 2010MY as the baseline, the agencies are not aware of DCP being applied to the Class 2b and 3 segment . However, the agencies note that multiple DCP equipped engines are currentl y available in the light duty counterparts to these vehicles implying thi s technology

may crossover to the light heav y dut y s egment in the near future. 2.3.1.4 **Cylinder Deactivation**  In conventional spark - ignited engines throttling the airflow controls engine torque output. At partial loads, efficiency can be improved by

using cylinder deactivation instead of throttling. Cylinder deactivation can improve engine efficiency by d isabling or deactivating (usually) half of the cylinders when the load is less than half of the engine’s total torque capability

– the valves are kept closed, and no fuel is injected

– as a result, the trapped air within the deactivated cylinders is simply compressed and expanded as an air spring, with reduced friction and heat losses. The active cylinders combust at almost double the load required if all of the cylinders were operating. Pumping losses are significantly reduced as long as the engine is op erated in this “part - cylinder” mode. Cylinder deactivation control strategy relies on setting maximum manifold absolute pressures or predicted torque within which it can deactivate the cylinders. Noise and vibration issues reduce the operating range to which cylinder deactivation is allowed, although manufacturers are exploring vehicle changes that enable increasing the amount of time that cylinder deactivation might be suitable. Some manufacturers may choose to adopt active engine mounts and/or active n oise cancellations sy stems to address NVH concerns and to allow a greater operating range of activation. 2.3.1.5 **Effectiveness improvements scale roughly with engine displacement -**  **to -**  **vehicle weight ratio: the higher displacement**  **- to**  **- weight vehicles, operating at l**  **ower relative loads for normal driving, have the potential to operate in part**  **- cylinder**  **mode more frequently. While several manufacturers have adopted cylinder**  **deactivation in their light -**  **duty vehicles equipped with 8 cylinder engines, the**  **same or similar engine**  **s for heavy**  **- duty application do not utilize this**  **technology. Manufacturers discovered that in most**  **heavy -**  **duty applications, the opportunity**  **for benefits**  **from this technology**  **are greatly reduced**  **, due to the**  **regularly required high load operation for these work** **- oriented vehicles.**  **Cylinder deactivation is thus not part of the technology package on which the**  **standards this analysis for the**  **HD pickup and van segment**  **are predicated**  **. Stoichiometric Gasoline Direct Injection**  Stoichiometric gasoline direct injection (SGDI) engines inject fuel at high pressure directly into the combustion chamber (rather than the intake port in port fuel injection). SGDI requires changes to the injector design, an additional high pressure fuel pump, new fuel rails to handle the higher fuel pressures , and changes to the cylinder head and piston crown design. Direct injection of the fuel into the cylinder improves cooling of the air/fuel charge within the cylinder, which allows for higher compression ratios and increased thermody namic efficiency***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 17 without the onset of combustion knock. Recent injector design advances, improved electronic engine management sy stems and the introduction of multiple injection events per cylinder firing cycle promote better mixing of the air and fuel, enhance combustion rates , increase residual exhaust gas tolerance and improve cold start emissions. SGDIengines achieve higher power density

and match well with other technologies, such as boosting and variable valvetrain designs. Several manufacturers have recently introduced vehicles with SGDIengines, including GM and Ford , who have announced their plans to increase dramatically the number of SGDI engines in their light - duty portfolios. The 2012 - 2016 l ight - d

uty rule estimate d the range of effectiveness to be from 1 to 2 percent for SGDI. NHTSA and EPA reviewed this estimate for purposes of this HD vehicle rulemaking , and continue to find it accurate. The NHTSA and EPA cost estimates for SGDI take into account the changes required to the engine hardware, engine electronic controls, ancillary and Noise Vibration and Harshness (NVH) mitigation sy stems. Consistent with the 2012 - 2016 light - duty rule, the agencies estimate the cost of conversion to SGDI on a V8 engine at $ 481 ( 2009 $) for the 2014MY. This estimate includes a medium complex ity I CM of 1. 39 and flat - portion of the curve learning. Note that this technology was considered low complexity in the proposal but has been upgraded to medium complexity for the final anal ys is as a result of a more detailed review of what it involves . 

### 2.3.2 **Diesel Engines** Diesel engines in this class of vehicle have emissions characteristics that present challenges to meeting federal Tier 2 NO x emissions standards. It is a significant sy stems engineering challenge to maintain the fuel consumption advantage o f the diesel engine while meeting U.S. emissions regulations. Fuel consumption can be negatively impacted by emissions reduction strategies depending on the combination of strategies employed. Emission compliance strategies for diesel vehicles sold in the U.S. are expected to include a combination of improvements of combustion, air handling s ys tem, aftertreatment , and advanced sy stem control optimization . These emission control strategies are being introduced on Tier 2 light - dut y diesel vehicles today Some of the engine technologies are described in the L ight - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards Joint Technical Support Document. 18 Others are from the 201 0 NAS Report, Technologies and Approaches to Reducing the Fuel Consumption of Medium - and Heav y - Duty Vehicles . Several key advances in diesel technology have made it possible to reduce missions coming from the engine prior to aftertreatment. These technologies include engine friction and parasitic loss reduction, improved fuel sy stems (higher injection pressure and multiple - injection capability), advanced controls and sensors to optimize combustion and emissions performance, higher EGR levels and EGR cooling to reduce NOx, and advanced turbocharging sy stems.**Regulatory Impact Anal ysis** 

2 - 18

2.3.2.1 **Low Friction Lubricants** Consistent with the discussion above for gasoline engines (see Section 2.3.1.1 ), the agencies are expecting some engine changes to accommodate low friction lubricants. Based on the 2012 - 2016 MY l ight - duty final rule, and previously - received confidential manufacturer data, NHTSA and EPA estimated the effectiveness of low friction lubricants to be between 0 to 1 percent. In the 2012 - 2016 MY light - duty FRM, the agencies estimated the cost of moving to low friction lubricants at $3 per vehicle (2007$). That estimate included a markup of 1.11 for a low complexity

technology . For Class 2b and 3, we are using the same base estimate but have mark ed it up to 2009 dollars using the GDP price deflator and have used a markup of 1. 24 for a low complexity technology

to arrive at a value of $4 per vehicle. As in the light duty rule, learning effects are not applied to costs for this technology and, as s uch, this estimate applies to all model years. 19 , 20 2.3.2.2 **Engine Friction Reduction** Reduced friction in bearings, valve trains, and the piston - to - liner interface will improve efficiency . Friction reduction opportunities in the engin e valve train and at its roller/tappet interfaces exist for several production engines. In virtuall y all production engines, the piston at its skirt/cylinder wall interface, wrist pin and oil ring/cylinder wall interface offer opportunities for friction r eduction. Use of more advanced oil lubricant that could be available for production in the future may also eventuall y play a key role in reducing friction. An y friction reduction must be carefully developed to avoid issues with durability or performance capability. Estimations of fuel consumption improvements due to reduced friction range from 0 percent to 2 percent. 21 Consistent with the cost estimated for gasoline engines, the agencies estimate the cost of engine friction reduction at $ 15 per cylinder compliance cost ( 2009 $), including the low complexity

I CM of 1. 24 , for a MY 2014 vehicle (learning effects are not applied to engine friction reduction). This cost is multiplied by the number of engine cylinders. 2.3.2.3 **Combustion and Fuel Injection System Optimization**  More flexible fuel injection capability with higher injection pressure provides more opportunities to improve engine fuel effic i ency , while maintaining the same emission level. Combustion system optimization features sy stem leve l integration and match, which includes piston bowl, injector tip and the number of holes, and intake swirl ratio. Cummins reports a 9.1 percent improvement in fuel consumption compared to a 2007 baseline , while meeting Tier 2 Bin 5 emissions wh en the combustion and fuel injection sy stem are integrated with other technologies, such as advanced and integrated aftertreatment technology , and advanced air handling s ys tem . 22 Translating this improvement to the 2010 baseline HD pickup and van eng ine, this could result in 4 - 6 percent improvement assuming that 2010 baseline engine has 3 - 5 percent advantage in fuel econom y over a 2007 engine baseline. The cost for this technology includes costs associated with low temperature exhaust gas recirculatio n (see Section 2.3.2.4 ), improved turbochargers (see Section 2.3.2.5 ) and***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 19 improvements to other systems and components. These costs are considered collectively in our costing anal ys is and termed “diesel engine improvements.” The agencies have estimated the c os t of diesel engine improvements at $ 148 based on the cost estimates for several individual technologies presented in Table 2 - 10 for light HD engines. Specifically , the direct manufacturing costs we have estimated are: improved cylinder head, $9; turbo efficiency improvements, $16; EGR cooler improvements, $3; higher pressure fuel rail, $10; improved fuel injectors, $13; improved pistons, $2; and reduced valve train friction, $ 95 . All values are in 2009 dollars and are applicable in the 2014MY. Applying a low complexity I CM of 1. 24 results in a cost of $ 18 4 ( 2009 $) applicable in the 2014MY. We consider the flat portion of the learning curve to be appropriate for these technologies. 2.3.2.4 **Low Temperature Exhaust Gas Recirculation** Low temperature exhaust gas recirculation could be one of the options to improve engine performance. Most medium - duty vehicle diesel engines sold in the U.S. market today use cooled EGR, in which part of the exhaust gas is routed through a cooler (rejecting energy to the engine coolant) before being returned to the engine intake manifold. EGR is a technology

employed to reduce peak combustion temperatures and thus NOx . L ow temperature EGR uses a larger or secondary EGR cooler to achieve lower intake charge temperatures, which tend to further reduce NOx formation. L ow - temperature EGR can allow changes such as more advanced injection timing that will increase engine efficiency slightly more than 1 percent (NESCCAF/I CCT, 2009, p. 62). Because low - temperature EGR reduces the engine’s exhaust temperature, it may not be compatible with exhaust energy recovery sy stems such as turbocompound or a bottoming cycle. The agencies’ cost estimate for this technology is discussed in Section 2.3.2.3 . 2.3.2.5 **Turbocharger Technology** Compact two stage turbochargers can increase the boost level with wider operation range, thus improving engine thermal efficiency . Ford’s new developed 6.7LScorpion engine features a twin - compressor turbocharger23

. Cummins is also developing its own two stage turbochargers. 24 Itis expected that this ty pe of technology

will continue to be improved b y better system matching and develop ment of higher compressor and turbine efficiency . The agencies’ cost estimate for this technology is discussed in Section 2.3.2.3 . 2.3.2.6 **Reduction of Parasitic Loads** Accessories that are traditionally gear - or belt - driven by

a vehicle’s engine can be optimized and/or converted to electric power. Examples include the engine water pump, oil pump, fuel injection pump , air compressor, power - steering pump, cooling fans, and the vehicle’s air - conditioning s ys tem. Optimization and improved pressure regulation may significantl y reduce the parasitic load of the water, air and fuel pumps. Electrification may result in a red

uction in power demand, because electricall y - powered accessories (such as the air compressor or power steering) operate onl y when needed if they are electrically powered,**Regulatory Impact Anal ysis** 

2 - 20

but they impose a parasitic demand all the time if they are engine - driven. In other cases, such as cooling fans or an engine’s water pump, electric power allows the accessory to run at speeds independent of engine speed, which can reduce power consumption. Electrification of accessories can individually improve fuel consumption, but as a package on a hy brid vehicle it is estimated that 3 to 5 percent fuel consumption reduction is possible. The TIAX [2009, pg. 3 - 5] study

used 2 to 4 percent fuel consumption improvement for accessory electrification, with the understanding that electrific ation of accessories will have more effect in short haul/urban applications and less benefit in line - haul applications. Consistent with the 2012 - 2016 MY light - dut y rule (where this technology was referred to as “ improved accessories ” ), the agencies estimat e the cost for this technology at $ 93 ( 2009 $) for a 2014MY vehicle. This estimate includes a low complexity I CM of 1. 24 and flat - portion of the curve learning. 2.3.2.7 **Improved Aftertreatment Efficiency and Effectiveness**  Selec tive Catal yt ic Reduction (SCR) sy stems are used by several manufacturers to control NO x emissions. 2010 fuel consumption was reduced 3 to 4 percent when compared to 2009, depending upon the manufacturer [2009, TIAX]. Inthe proposal we estimated that a dditional improvements of 3 to 5 percent relative to 2010 may be reasonably

expected as sy stem effectiveness increases and accumulated knowledge is applied in calibration. We received no comments disagreeing with this assessment. Additionally , as SCR sy s tem effectiveness is improved, d iesel particulate filters (DPF s ) may be better optimized to reduced particulate loading (ability to run at higher engine out NO x), reducing the associated pressure drop associated with their presence in the exhaust sy stem. Such DPF changes may result in a 1.0

– 1.5 percent fuel consumption reduction25 The agencies have estimated the cost of this technology at $25 for each percentage improvement in fuel consumption from that of the baseline sy stems . This cost would cover the engineering and test cell related costs necessary to develop and implement the improved control strategies that would allow for the improvements in fuel consumption. Importantly , the engineering work involved would be expected to result in cost savings to the aftertreatment and control hardwar e (lower platinum group metal (PGM) loadings, lower reductant dosing rates, etc.). Those savings are considered to be included in the $25 per percent estimate described here. Given the average 4 percent expected improvement in fuel consumption results in an estimated cost of $ 119 ( 2009 $) for a 2014MY vehicle. This estimate includes a low complexity I CM of 1. 24 and flat - portion of the curve learning from 2012 forward. We did not receive negative comments on this cost estimate. 

### 2.3.3 **Drive Train** NHTSA and EPA have also reviewed the transmission technology estimates used in the 2012 - 2016 light - dut y final rule. In doing so, NHTSA and EPA considered or reconsidered all available sources and updated the estimates as appropriate. The section below describes each o f the transmission technologies considered for this rulemaking.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 21 2.3.3.1 **Improved Automatic Transmission Control (IATC) (Aggressive Shift Logic and Early Torque Converter Lockup)**  Calibrating the transmission shift schedule to upshift earlier and quicker, and to loc k up or partiall y lock up the torque converter under a broader range of operating conditions can reduce fuel consumption and CO 2 emissions. However, this operation can result in a perceptible degradation in noise, vibration, and harshness (NVH). The de gree to which NVH can be degraded before it becomes noticeable to the driver is strongl y influenced b y characteristics of the vehicle, and although it is somewhat subjective, it alway s places a limit on how much fuel consumption can be improved by transmis sion control changes. Given that the Aggressive Shift Logic and Earl y Torque Converter Lockup are best optimized simultaneously

due to the fact that adding both of them primarily requires only

minor modifications to the transmission or calibration software, these two technologies are combined in the modeling. 2.3.3.2 **Aggressive Shift Logic** During operation, an automatic transmission’s controller manages the operation of the transmission by

scheduling the upshift or downshift, and locking or allowing the torque co nverter to slip based on a preprogrammed shift schedule. The shift schedule contains a number of lookup table functions, which define the shift points and torque converter lockup based on vehicle speed and throttle position, and other parameters such as t emperature. Aggressive shift logic (ASL) can be employed in such a way as to maximize fuel efficiency by modifying the shift schedule to upshift earlier and inhibit downshifts under some conditions, which reduces engine pumping losses and engine friction. The application of this technology

does require a manufacturer to confirm that drivability , durability , and NVH are not significantl y degraded. We consider this technology to be present in the baseline 6 - speed automatic transmissions in the majority of C lass 2b and 3 trucks in the 2010 model year timeframe , and thus do not include it in the package of technologies on whose use the stringency of the standard is predicated . 2.3.3.3 **Early Torque Converter Lockup** A torque converter is a flu id coupling located between the engine and transmission in vehicles with automatic transmissions and continuously - variable transmissions (CVT). This fluid coupling allows for slip so the engine can run while the vehicle is idling in gear (as at a stop light), provides for smoothness of the powertrain, and also provides for torque multiplication during acceleration, and especiall y l aunch. During light acceleration and cruising, the inherent slip in a torque converter causes increased fuel consumption, so m odern automatic transmissions utilize a clutch in the torque converter to lock it and prevent this slippage. Fuel consumption can be further reduced by locking up the torque converter at lower vehicle speeds, provided there is sufficient power to propel the vehicle, and noise and vibration are not excessive. If the torque converter cannot be full y locked up for maximum efficiency , a partial lockup strategy can be emplo yed to reduce slippage. Early torque**Regulatory Impact Anal ysis** 

2 - 22

converter lockup is applicable to all vehicle typ e s with automatic transmissions. Some torque converters will require upgraded clutch materials to withstand additional loading and the slipping conditions during partial lock - up. As with aggressive shift logic, confirmation of acceptable drivability, perf ormance, durability

and NVH characteristics is required to successfull y implement this technology. We consider this technology to be present in the baseline, 6 - speed automatic transmissions in the majority of C lass 2b and 3 trucks in the 2010 model year ti meframe , and thus do not include it in the package of technologies on whose use the stringency of the standard is predicated . 2.3.3.4 **Automatic 6 -**  **and 8 -**  **Speed Transmissions** Manufacturers can also choose to replace 4 - and 5 - speed transmissi on with 6 - or 8 - speed automatic transmissions. Additional ratios allow for further optimization of engine operation over a wider range of conditions, but this is subject to diminishing returns as the number of speeds increases. As additional planetary ge ar sets are added (which may be necessary in some cases to achieve the higher number of ratios), additional weight and friction are introduced. Also, the additional shifting of such a transmission can be perceived as bothersome to some consumers, so manuf acturers need to develop strategies for smooth shifts. Some manufacturers are replacing 4 - and 5 - speed automatics with 6 - speed automatics, and 7 - and 8 - speed automatics have also entered production, albeit in lower - volume applications in luxury

and perfor

mance oriented cars. As discussed in the 2012 - 2016 light - dut y final rule, confidential manufacturer data projected that 6 - speed transmissions could incrementally reduce fuel consumption by 0 to 5 percent from a baseline 4 - speed automatic transmission, whil e an 8 - speed transmission could incrementall y reduce fuel consumption by up to 6 percent from a baseline 4 - speed automatic transmission. GM has publicly claimed a fuel economy

improvement of up to 4 percent for its new 6 - speed automatic transmissions 26

. NHTSA and EPA reviewed and revised these effectiveness estimates based on usage and testing methods for Class 2b and 3 vehicles along with confidential business information. When combined with IATC, the agencies estimate the effectiveness for a conversion from a 4 to a 6 - speed transmission to be 5.3 percent and a conversion from a 6 to 8 - speed transmission to be 1.7 percent . As for costs, the agencies have considered the recent study conducted b y NAS (NAS 2010) which showed an incremental cost of $210 for an 8 speed automatic transmission relative to a 6 speed automatic transmission (the baseline technology for 2010MY Class 2b & 3 pickups and vans). Considering this to be a valid cost for 2012MY and applying a low complexity

I CM of 1. 24 result s in a cost of $ 294 in 2012. Considering flat - portion of the curve learning to be appropriate for automatic transmissions and applying two years of learning results in a 2014MY cost of $ 281 ( 2009 $). This technology is considered applicable to both gasoline and diesel trucks and vans.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 23 2.3.3.5 **Electric Power Steering/Electro -**  **hydraulic Power Steering (EPS/EHPS)** Electric power steering (EPS) or Electroh ydraulic power steering (EHPS) provides a potential reduction in CO2 emissions and fuel consumption over hydra ulic power steering because of reduced overall accessory loads. This eliminates the parasitic losses associated with belt - driven power steering pumps which consistently draw load from the engine to pump hydraulic fluid through the steering actuation sy ste ms even when the wheels are not being turned. EPS is an enabler for all vehicle h ybridization technologies since it provides power steering when the engine is off. EPS may be implemented on most vehicles with a standard 12V sy stem. Some heavier vehicles may require a higher voltage s ys tem which may add cost and complexity . The 2010 light - dut y final rule estimated a 1 to 2 percent effectiveness based on the 2002 NAS report, a Sierra Research report, and confidential manufacturer data. NHTSA and EPA revie wed these effectiveness estimates and found them to be accurate, thus they have been retained for this final rule. NHTSA and EPA adjusted the EPS cost for the current rulemaking based on a review of the specification of the sy stem. Adjustments were made t o include potentially higher voltage or heavier dut y s ys tem operation for Class 2b and 3. Accordingl y, higher costs were estimated for s ys tems with higher capability . After accounting for the differences in s ys tem capability and appl yi ng the I CM markup o f low complexity technology

of 1. 24 , the estimated costs for this rulemaking are $ 115 for a MY 2014 truck or van ( 2009 $). As EPS sy stems are in widespread usage today, flat - portion of the curve learning is deemed applicable. EHPS sy stems are considered t o be of equal cost and both are considered applicable to gasoline and diesel engines. 2.3.3.6 **Hybrids** Commenters arguing for more stringent standards cited the 2010 NAS study (and an associated TIAX report) finding that technologies such as h ybridization are feas ible. However, in the ambitious timeframe we are focusing on for these rules, targeting as it does technologies implementable in the HD pickup and van fleet starting in 2014 and phasing in with normal product redesign cycles through 2018, our assessment s hows that the standards we are establishing , which are not based on significant hy bridization, are appropriate. More advanced technologies considered in the NAS report would be appropriate for consideration in future rulemaking activity . 

### 2.3.4 **Aerodynamics** Aerodynamic drag is an important aspect of the power requirements for Class 2b and 3 trucks. Because aerodyn amic drag is a function of the cube of vehicle speed, small changes in the aerodyn amics of a Class 2b and 3 can reduce drag, fuel consumption, and GHG emissions. Some of the opportunities to reduce aerodyn amic drag in Class 2b and 3 vehicles are similar**Regulatory Impact Anal ysis** 

2 - 24

to those in Class 1 and 2 (i.e., light - dut y) vehicles. In general, these transferable features make the cab shape more aerodynamic b y streamlining the airflow over the bumper, grill, windshield, sides, and roof. Class 2b and 3 vehicles may also borrow from light - duty vehicles certain drag reducing accessories (e.g., streamlined mirrors, operator steps, and sun visors). The great variety of applicati ons for Class 2b and 3 trucks result in a wide range of operational speed profiles (i.e., in - use drive cycles) and functional requirements (e.g., shuttle buses that must be tall enough for standing passengers, trucks that must have racks for ladders). Thi s variet y makes it challenging to develop aerodyn amic solutions that consider the entire vehicle. Consistent with the 2012 - 2016 light - dut y rule, the agencies have estimated the cost for this technology

at $ 58 ( 200 9 $) including a low complexity I CM of 1. 24 . This cost is applicable in the 201 4 model year to both gasoline and diesel trucks and vans and is considered to be on the flat - portion of the learning curve . 

### 2.3.5 **Tires** Ty pically , tires used on Class 2b/3 vehicles are not designed specifically for the vehicle . These tires are designed for broader use and no single parameter is optimized. Similar to vocational vehicles, the market has not demanded tires with improved rolling resistance thus far ; therefore, manufacturers have not traditionally designed tires wi th low rolling resistance for Class 2b/3 vehicles. EPA and NHTSA believe that a regulatory program that incentivizes the optimization of tire rolling resistance, traction and durability can bring about GHG emission and fuel consumption reductions from th is segment. Based on the 2012 - 2016 Light - dut y final rule and the 2010 NAS report, the agencies have estimated the cost for low rolling resistance tires to be $ 7 (2009$) per Class 2b truck or van, and $ 10 (2009$) per Class 3 truck or van. 27 The higher cost for the Class 3 trucks and vans is due to the predominant use of dual rear tires and, thus, 6 tires per truck. Due to the commodity - based nature of this technology , cost reductions due to learning are not applied. This technology

is co nsider ed applicable to both gasoline and diesel. 

### 2.3.6 **Mass Reduction** Reducing a vehicle’s mass, or down - weighting the vehicle, decreases fuel consumption by

reducing the energy

demand needed to overcome forces resisting motion, and rolling resistance. Manufa cturers employ a s ys tematic approach to mass reduction, where the net mass reduction is the addition of a direct component or sy stem mass reduction plus the additional mass reduction that can be taken from indirect ancillary s ys tems and components, as a re sult of full vehicle optimization, effectively compounding or obtaining a secondary mass reduction from a primary mass reduction. For example, use of a smaller, lighter engine with lower torque - output subsequently allows the use of a smaller, lighter - weight transmission and drive line components. Likewise, the compounded weight reductions of the body , engine and drivetrain reduce stresses on the suspension components, steering components, wheels, tires and brakes, allowing further reductions in the mass o f these subsy stems. The reductions in unsprung masses such as brakes, control arms, wheels and***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 25 tires further reduce stresses in the suspension mounting points. This produces a compounding effect of mass reductions. Estimates of the sy

nergistic effects of mass reduction and the compounding effect that occurs along with it can vary significantl y from one report to another. For example, in discussing its estimate, an Auto - Steel Partnership report states that “These secondary mass changes can be considerable

— estimated at an additional 0.7 to 1.8 times the initial mass change.” 28 This means for each one pound reduction in a primary component, up to 1.8 pounds can be reduced from other structures in the vehicle ( i.e. , a 180 percent factor). The report also discu sses that a primary variable in the realized secondary weight reduction is whether or not the powertrain components can be included in the mass reduction effort, with the lower end estimates being applicable when powertrain elements are unavailable for mas s reduction. However, another report b y the Aluminum Association, which primarily focuses on the use of aluminum as an alternative material for steel, estimated a factor of 64 percent for secondary mass reduction even though some powertrain elements were considered in the anal ys is. 29 That report also notes that ty pical values for this factor vary from 50 to 100 percent. Although there is a wide variation in stated estimates, sy nergistic mass reductions do exist, and the effects result in tangible mass red uctions. Mass reductions in a single vehicle component, for example a door side impact/intrusion sy stem, may actuall y result in a significantl y higher weight savings in the total vehicle, depending on how well the manufacturer integrates the modification into the overall vehicle design. Accordingl y, care must be taken when reviewing reports on weight reduction methods and practices to ascertain if compounding effects have been considered or not. Mass reduction is broadly applicable across all vehicle subs ys tems including the engine, exhaust system, transmission, chassis, suspension, brakes, body , closure panels, glazing, seats and other interior components, engine cooling s ys tems and HVAC s ys tems. It is estimated that up to 1.25 kilograms of secondary wei ght savings can be achieved for every kilogram of weight saved on a vehicle when all subs ys tems are redesigned to take into account the initial primary weight savings. 30 , 31 Mass reduction can be accomplished by proven methods such as:  Smart Design: Comput er aided engineering (CAE) tools can be used to better optimize load paths within structures b y reducing stresses and bending moments applied to structures. This allows better optimization of the sectional thicknesses of structural components to reduce ma ss while maintaining or improving the function of the component. Smart designs also integrate separate parts in a manner that reduces mass by combining functions or the reduced use of separate fasteners. In addition, some “body on frame” vehicles are rede signed with a lighter “unibody” construction.  Material Substitution: Substitution of lower density and/or higher strength materials into a design in a manner that preserves or improves the function of the component. This includes substitution of high - strength steels, aluminum, magnesium or composite materials for components currentl y fabricated from mild steel.**Regulatory Impact Anal ysis** 

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 Reduced Powertrain Requirements: Reducing vehicle weight sufficientl y al lows for the use of a smaller, lighter and more efficient engine while maintaining or increasing performance. Approximately half of the reduction is due to these reduced powertrain output requirements from reduced engine power output and/or displacement, changes to transmission and final drive gear ratios. The subsequent red uced rotating mass ( e.g. , transmission, driveshafts/halfshafts, wheels and tires) via weight and/or size reduction of components are made possible by reduced torque output requirements.  Automotive companies have largely used weight savings in some vehicle subsy stems to offset or mitigate weight gains in other subs ys tems from increased feature content (sound insulation, entertainment sy stems, improved climate control, panoramic roof, etc.).  Li ghtweight designs have also been used to improve vehicle performa nce parameters by increased acceleration performance or superior vehicle handling and braking. Many manufacturers have already announced final future product plans reducing the weight of a vehicle body through the use of high strength steel body - in - white, composite body panels, magnesium allo y front and rear energy absorbing structures reducing vehicle weight sufficiently

to allow a smaller, lighter and more efficient engine. Nissan has stated that it will be reducing average vehicle curb weight by 15% b y 2015. 32 Ford has identified weight reductions of 250 to 750 lb per vehicle as part of its implementation of known technology within its sustainability

strategy between 2011 and 2020. 33 Mazda has stated that it plans to reduce vehicle weight by 220 pounds per vehicle or more as models are redesigned. 34 , 35 Ducker International estimates that the average curb weight of light - dut y vehicle fleet will decrease approximately

2.8% from 2009 to 2015 and approximately 6.5% from 2009 to 2020 via changes in automotive materials and increased change - over from previously used body on - frame automobile and light - truck designs to newer unibody designs. 32 While the opportunity

for mass reductions available to the light - dut y fleet may not in all cases be applied directl y to the heavy - duty fleet due to the different designs for the expected duty cycles of a “work” vehicle, mass reductions are still available , particularly to areas unrelated to the components and s ystems necessary for the work vehicle aspects. Due to the payload and towing requirements of these heav y - dut y vehicles, engine downsizing was not considered in the estimates for CO 2 reduction in the area of mass reduction and material substitution. NHTSA and EPA estimate that a 3 percent mass reduction with no engine downsizing results in a 1 percent reduction in fuel consumption. In addition, a 5 and 10 percent mass reduction with no engine downsizing result in an estimated CO 2 reduction of 1.6 and 3.2 percent respectively . These effectiveness values are 50% of the 2012 - 2016 light - dut y final rule values due to the elimination of engine downsizing for this class of vehicle. The agencies have recently completed work on an Interim Joint Technical Assessment Report (TAR) that considers light - dut y GHG and fuel econom y standards for the years 2017 through 2025 and have continued this wo rk for the proposed light - duty vehicle rule . Based on new information from various industry and literature sources, the TAR report modified the mass reduction/cost relationship used in the 2012 - 2016 light - duty final rule to begin at the***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 27 origin (0% weight reduction) and to have increasing cost with increasing mass reduction. B The resulting anal ys is showed costs for 5% mass reduction on light - dut y vehicles to be near zero or cost parit y. At proposal for heavy - duty vehicles, we estimated mass r eduction costs based on the 2012 - 2016 light - dut y analy sis without accounting for the new work completed in the Interim Joint Technical Assessment. Since the proposal, we have been able to consider our cost estimates here in the context of both light - duty and heavy - dut y vehicle bodies of work. For this final action, in aggregate, we estimate a 5 percent mass reduction at a cost of $80 - 100 per vehicle. We are estimating the following direct manufacturer costs for a 5% mass reduction; Class 2b gasoline $ 85 , 2b diesel $ 95 , 3 gasoline $ 90 , 3 diesel trucks $100. In cluding a low complexity

I CM of 1.24 and using learning on the flat portion of the curve, these values become $103, $115, $ 109 and $121, respectivel y, applicable in the 2016 MY and expressed in 2009 dollars . This estimate is higher than our most recent estimate of mass reduction contained in the light - duty vehicle Interim Joint Technical Assessment Report because we do not believe that all of the weight reduction opportunities for light - dut y vehicles can be applied to heav y - dut y trucks. However, we do believe reductions in the following components and sy stems can b e found that do not affect the payload and towing requirements of these heav y duty vehicles; body , closure panels, glazing, seats and other interior components, engine cooling s ys tems and HVAC sy stems. 

### 2.4 **Heavy -**  **Duty Engines** The regulatory

structure for heav y - dut y engines separates the compression ignition (or “diesel”) engines into three regulatory subcategories and from spark ignition (or “gasoline”) engines into a single regulatory subcategory . Therefore, the subsequent discussion will assess each t ype of engine separately. The l ight - h eav y - d

ut y d iesel engines ty

picall y range between 4.7 and 6.7 liters displacement, the m edium - h eav y - d ut y d iesel engines ty

pically have some overlap in displacement with the l ight - h eav y - d ut y d iesel engines and range between 6.7 and 9.3 liters. The h eav y - h eav y - d

uty d iesel engines t ypicall y are represented b y engines between 10.8 and 16 liters. The heav y - duty gasoline engines have ranged in the past between 4.8 and 8.1 liters. 

### 2.4.1 **Spark Ignition Engines** Spark ignition engines are certified for the heav y - duty market. These engines have historically range d in displacement between five and eight liters and are either V8 or V10 configurations. As found in the 2010 NAS study , most are either V8 or V10 engines with port fuel injection, naturally aspirated with fixed valve timing s. Most recently , the primary

B “Interim Joint Technical Assessment Report: Light - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards for Model Years 2017 - 2025 ;” September 2010; available at http://epa.gov/otaq/climate/regulations/ldv - ghg - tar.pdf and in the docket for this rule.**Regulatory Impact Anal ysis** 

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producers of the gasoline engines were limited to Ford and General Motors. The engines sold separately , which require an engine certificate in lieu of a chassis certificate, are the same as or very similar to the engines used in the pick up truck and vans. Therefore, NHTSA and EPA developed the baseline list of engine technologies and standards to reflect this commonality . 2.4.1.1 **Baseline SI Engine CO 2**  **and Fuel Consumption** Similar to the gasoline engine used as the baseline in the L ight - Dut y GHG rule (an assumption not questioned in the comments to that rulemaking), the agencies assumed the baseline engine in this segment to be a naturall y aspirated, single overhead valve V8 engine. The following discussion of effectiveness is generally in comparison to 2010 baseline engine performance. NHTSA and EPA developed the baseline fuel consumption and CO 2 emissions for the gasoline engines from manufacturer - reported CO 2 values used in the certification of non GHG pollutants. The baseline engine for the analysis was developed to represent a 2011 model year engine, because this is the most current information available. The average CO 2 performance of the heavy - dut y gasoline engines was 660 g/bhp - hour, which will be used as a baseline. 2.4.1.2 **Gasoline Engine Technologies** The engine technologies projected for the gasoline heav y - dut y engines are based on the technologies used in the L ight - Duty Vehicle Greenhouse Gas Emission Standards and Co rporate Average Fuel Economy Standards Joint Technical Support Document. 37 The effectiveness of the technology packages were evaluated using the EPA Lumped Parameter model HD Version 1.0.0.1. 38 The HD version of the Lumped Parameter model includes a subset of the technologies included in the Large Pickup Truck version of the L ight - Duty rulemaking to recognize that some technologies will have limited effectiveness due to the higher operating weights of these trucks. The HD Lumped Parameter model also has re duced the effectiveness of several of the remaining individual technologies , again to recognize the higher test weights used in regulatory programs. **2.4.1.2.1 Engine Friction Reduction**  In addition to low friction lubricants, manufacturers can also reduce friction and improve fuel consumption by improving the design of engine components and subsy stems. Examples include improvements in low - tension piston rings, piston skirt design, roller cam followers, improved crankshaft design and bearings, material coatings, mate rial substitution, more optimal thermal management, and piston and cylinder surface treatments. Additionally , as computer - aided modeling software continues to improve, more opportunities for evolutionary

friction reductions may

become available. All recip rocating and rotating components in the engine are potential candidates for friction reduction, and minute improvements in several components can add up to a measurable fuel economy improvement. The 2012 - 2016 MY light - duty rule, 2010 NAS Report, and the N ESCCAF and EEA reports , as well as confidential manufacturer data suggested a range of effectiveness for engine***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 29 friction reduction to be between 1 to 3 percent. NHTSA and EPA continue to believe that this range is accurate . NHTSA and EPA believe that the cost estimate is closer to the lower end of the model ye ar (MY) 2011 CAFE final rule range and thus for this rulemaking are projecting $ 10 per cylinder compliance cost (200 9 $), plus a low complexity Indirect Cost Multiplier (I CM) markup value of 1. 24 , for a MY 2016 engine (learning effects are not applied to engine friction reduction). This cost is multiplied by the eight cylinders resulting in a cost of $ 95 ( 2009 $) per engine for this technology . **2.4.1.2.2 Coupled Cam Phasing**  Valvetrains with coupled (or coordinated) cam phasing (CCP) can modify the timing of both the inlet valves and the exhaust valves an equal amount by phasing the camshaft of a single overhead cam (SOHC) engine or an overhead valve (OHV) engine. For overhead cam engines, this requires the addi tion of a cam phaser on each bank of the engine so SOHC V engines have two cam phasers. For overhead valve (OHV) engines, which have onl y one camshaft to actuate both inlet and exhaust valves, CCP is the only variable valve timing (VVT) implementation opti on available and requires only one cam phaser. Current overhead cam engines in the heav y duty sector contain a single camshaft per head which ty pically requires a phaser per cam or two per engine . Based on 2010 L ight - Dut y final rule, previouslyrece ived confidential manufacturer data, and the NESCCAF report, NHTSA and EPA estimated the effectiveness of CCP to be between 1 to 4 percent. NHTSA and EPA reviewed this estimate for purposes of this rulemaking , and continue to find it accurate. Co nsistent with the 2010 2012 - 2016 L ight - Duty final rule, NHTSA and EPA estimate the cost of a cam phase r at $ 49 ( 200 9 $) in the 2014MY. This estimate includes a low complexity

I CM of 1. 24 . With two years of flat - portion of the curve learning this cost becomes $ 46 ( 2009 $) in the 2016MY. The majority of heavy - dut y gasoline loose engines are over - head valve engines (OHV) and, as such, would require onl y one cam phaser for coupled cam phasing. The most recentl y designed engines, b oth overhead valve and overhead cam installed in heavy - dut y pickup trucks and vans contain coupled cam phasing and are expected in the future to replace any legacy loose engines. **2.4.1.2.3 Cylinder Deactivation**  In conventional spark - ignited engines throttling the airflow controls engine torque output. At partial loads, efficiency can be improved by

using cylinder deactivation instead of throttling. Cylinder deactivation (DEAC) can improve engine efficiency by disabling or deactivating (usuall y) half of the cylinde rs when the load is less than half of the engine’s total torque capability

– the valves are kept closed, and no fuel is injected

– as a result, the trapped air within the deactivated cylinders is simply compressed and expanded as an air spring, with reduce d friction and heat losses. The active cylinders combust at almost double the load**Regulatory Impact Anal ysis** 

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required if all of the cylinders were operating. Pumping losses are significantly reduced as long as the engine is operated in this “part cylinder” mode. Cylinder deactivat ion control strategy relies on setting maximum manifold absolute pressures or predicted torque within which it can deactivate the cylinders. Noise vibration and harshness (NVH) issues reduce the operating range to which cylinder deactivation is allowed, al though manufacturers are exploring vehicle changes that enable increasing the amount of time that cylinder deactivation might be suitable. Some manufacturers may choose to adopt active engine mounts and/or active noise cancellations sy stems to address NVH concerns and to allow a greater operating range of activation. Cylinder deactivation has seen a recent resurgence thanks to better valvetrain designs and engine controls. General Motors and Chry sler Group have incorporated cylinder deactivation across a su bstantial portion of their V8 - powered lineups in the light - dut y market . Effectiveness improvements scale roughl y with engine displacement - to - vehicle weight ratio: the higher displacement - to - weight vehicles, operating at lower relative loads for normal driving, have the potential to operate in part - cylinder mode more frequently . Cylinder deactivation is less effective on heavil y - loaded vehicles because they require more power and spend less time in areas of operation where onl y partial power is required . The technology also requires proper integration into the vehicles which i s difficult in the vocational vehicle segment where often the engine is sold to a chassis manufacturer or body builder without knowing the t ype of transmission or axle used in the vehicle or the precise duty cycle of the vehicle. The cylinder deactivation requires fine tuning of the calibration as the engine moves into and out of deactivation mode to achieve acceptable NVH. Additionally , c yl inder deactivation would be difficult to apply to vehicles with a manual transmission because it requires careful ge ar change control. NHTSA and EPA adjusted the 2010 light - duty final rule estimates using updated power to weight ratings of heav y - dut y trucks and confidential business information and downwardl y adjusted the effectiveness to 0 to 3 percent for these vehic les to reflect the differences in drive cycle and operational opportunities compared to light - duty vehicles Unlike light - dut y , cylinder deactivation is not expected to penetrate the heav y - dut y sector due to the unique duty cycle resulting in lower effect iveness. **2.4.1.2.4 Stoichiometric gasoline direct injection**  **(SGDI)** SGDIengines inject fuel at high pressure directl y into the combustion chamber (rather than the intake port in port fuel injection). SGDIrequires changes to the injector design, an additional high - pressure fuel pump, new fuel rails to handle the higher fuel pressures and changes to the cylinder head and piston crown design. Direct injection of the fuel into the cylinder improves cooling of the air/fuel charge within the cylinder, which allows for higher compression ratios and increased thermody namic efficiency

without the onset of combustion knock. Recent injector design advances, improved electronic engine management sy stems and the introduction of multiple injection events per cylinder firing cycle promote better mixing of the air and fuel, enhance combustion rates, increase residual exhaust gas tolerance and improve cold start emissions. SGDIengines achieve higher power density and match well with other technologies, such as boosting and variable valvetrain designs. NHTSA***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 31 and EPA continue to agree with estimate d effectiveness of SGDI in the range of 1 to 2 percent improvement for SGDI. The NHTSA and EPA cost estimates for SGDI take into account the changes required to the engine hardware, engine electronic controls, ancillary and NVH mitigation sy stems. The NHTSA and EPA cost estimates for SGDI take into account the changes required to the engine hardware, engine electronic controls, ancillary and Noise Vibration and Harshness (NVH) mitigation sy stems In the proposal, c onsistent with the 2012 - 2016 light duty rule, the agencies estimate d the cost of conversion to SGDIon a V8 engine at $395 (2008$) for the 2014MY including a low complexity I CM of 1.17 . For this final anal ys is, based on further review, we have changed the complexity le vel of this technology

to medium and, with the markup of 1.39 the cost becomes $474 (2009$) in the 2014MY. We consider flat - portion of the curve learning to be appropriate for this technology so the cost becomes $452 (2009$) for the 2016MY. SIEngine Technology Package The average CO 2 performance of the two heav y - duty gasoline engines certified for 2010 and 2011 model years was 660 g CO 2 /bhp - hour. The HD Lumped Parameter model anal ys is projects that the package of the three technologies (friction reduction, closed couple cam phasing, and stoichiometric direct injection) could reduce CO 2 emissions and fuel consumption by

5 percent. Therefore, the agencies are finalizing the standard in 2016 model ye ar at 627 g CO 2 /b hp - hr. 2.4.1.3 **SI Engine Technology Cost** As shown in Table 2 - 5 , the overall projected engine package cost for a 2016 model ye ar engine is $ 594 ( 2009 $).

**Table 2**  **- 5**  **Estimated 2016MY Costs for a Spark -**  **Ignition HD Engine ( 2009**  **dollars)** DIRECT MFG COST ICM MARKED UP COSTS Engine Friction Reduction $76 1. 24 $ 95 Coupled Cam Phasing (OHV) a $37 1. 24 $ 46 Stoichiometric Gas Direct Injection $ 321 1. 39 $ 452 Total $ 435 $ 594 a Note: the direct manufacturing cost of cam phasing would be $74for engines with dual cams. 

### 2.4.2 **Diesel Engines** 2.4.2.1 **Baseline Engines** The agencies developed the baseline diesel engine as a 2010 model year engine with an aftertreatment s ys tem which meets EPA’s 0.2 0 grams of NOx/bhp - hr standard with a selective catal yt ic reduction (SCR) sy stem along with EGR and meets the PM emissions standard with a diesel particulate filter (DPF) with active regeneration. The engine is**Regulatory Impact Anal ysis** 

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turbocharged with a variable geometry turbocharger , based on the agencies’ assessment of today ’s engines . The following discussion of technologies describes improvements over the 2010 model year baseline engine pe rformance, unless otherwise noted. The CO 2 performance over the FTP for the baseline engines were developed through manufacturer reporting of CO 2 in their non - GHG certification applications for 2010 model ye ar. This data was carefully considered to e ns ure that the baseline represented an engine meeting the 0.2 0 g/bhp - hr NOx standard. For those engines that were not at this NOx level or higher, then the agencies derived a CO 2 correction factor to bring them to a 0.2 0 g/bhp - hr NOx emissions. The CO 2 correction factor is derived based on available experimental data obtained from manufacturers and public literature. The agencies then sales - weighted the CO 2 performance to derive a baseline CO 2 performance for each engine subcategory . In order to establ ish baseline SET performance for the Heav y Heav y - Dut y and Medium Heav y - Dut y Diesel Engines, several sources were considered. Some engine manufacturers provided the agencies with SET modal results or fuel consumption maps to represent their 2009 model year engine fuel consumption performance. As a supplement to this, complete engine map CO 2 data (including SET modes) acquired in EPA test cells were also considered. The pre - 2010 maps are subsequently adjusted to represent 2010 model year engine maps by

usin g predefined technologies , includ ing SCR and other advanced sy stem s that are being used in current 2010 production. In summary , the baseline CO 2 performance for each diesel engine category is included in Table 2 - 6 . **Table 2**  **- 6**  **: Baseline CO 2**  **Perform ance (g/bhp**  **- hr)**  LHDD - FTP MHDD - FTP HHDD - FTP HHDD - SET 630 630 584 490 The agencies used the baseline engine to assess the potential of each of the following technologies. 2.4.2.2 **Combustion System Optimization** Continuous improvements on the fuel injection sy stem allows more flexible fuel injection capability

with higher injection pr essure, which can provide more opportunities to improve engine fuel efficiency , while maintaining the same emission level. Combustion sy stem optimization, featuring piston bowl, injector tip and the number of holes, in conjunction with the advanced fuel injection s ys tem, is able to further improve engine performance and fuel efficiency . At this point, all engine manufacturers are spearhead ing substantial efforts into this direction in the hope that their development efforts would be translate d into production in the near futures. Some examples include the combustion development programs conducted b y Cummins 39 and Detroit Diesel 40 funded by Department of Energy . Cummins and Detroit Diesel both claim that 10 percent thermal efficiency improvement at 2010 emission level is achievable. While their findings are still more towards research environment, their results do enhance the possibility that some of technologies they are developing could be applied to production in the time frame of 2 017. The agencies have***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 33 determined that up to a 2 .5 percent reduction in fuel consumption and CO 2 emissions is feasible in the 2017 model year through the use of these technologies. The cost for this technology includes costs associated with several individual technologies , s pecifically, improved cylinder head, turbo efficiency improvements, EGR cooler improvements, higher pressure fuel rail, improved fuel injectors and improved pistons. The cost estimates for each of these technologies are pre sented in Table 2 - 8 through Table 2 - 10 for heav y HD, medium HD and light HD en gines, respectivel y. The agencies consider a low complexity

I CM of 1.1 5 and flat - portion of the curve learning from 2014 forward to be appropriate for these technologies. Significant progress on advanced engine control ha s been made in the past few ye ars , including model based calibration . Detroit Diesel introduced the next generation model based control concept, achieving 4 percent thermal efficiency improvement while simultaneously reducing emissions in transient operations. 41 Their model based concept features a series of real time optimizers with multiple inputs and multiple outputs. This controller contains many phy sical based models for engine and aftertreatment. It produces full y transient engine performance and emissio ns predictions in a real - time manner. Although this control concept may still not be mature in 2014 production, it would be a realistic estimate that this ty pe of real time model control could be in production before 2017, thus significantly improving engi ne fuel econom y. The agencies have included the costs of control development in the research and development costs applied separatel y to each engine manufacturer. 2.4.2.3 **Turbocharg ing and Air Handling System**  Many advanced turbocharger technologies can be potenti ally added into production in the time frame between 2014 and 2017, and some of them are already in production , such as m echanical or electric turbocompound, two - stage turbochargers with intercooler, and high efficient low speed compressor . A turbocompound sy stem extracts energy from the exhaust to provide additional power. Mechanical turbocompounding includes a power turbine located downstream of the turbine which in turn is connected to the crankshaft to supply additional power. As noted in the 2010 NAS report, it typically includes a fluid coupling (to allow for speed variation and to protect the power turbine from engine torsional vibration) and a gear set to match power turbine speed to crankshaft speed. Turbocompound has been used in production by Detroit Diesel for their DD15 and DD16 engines and they claim a 3 to 5 percent fuel consumption reduction due to the s ys tem. 42 The 2010 NAS report 43 includes published information from four sources on the fuel consumption reduction fro m mechanical turbocompounding ranging from 2.5 to 5 percent. Some of these differences may depend on the operating condition or duty cycle that was considered b y the different researchers. The performance of a turbocompound sy stem tends to be best at full load , and it can be much less effective, or even act as an energy

sink , to suck the energy

at light loads. Because of that, a clutch that can separate the engine crankshaft from turbocompound gear train could be put into production in order to overcome th e drawbacks of turbocompound at light loads, thus improving fuel effic ie ncy over the entire speed and load ranges. The agencies have assessed mechanical**Regulatory Impact Anal ysis** 

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turbocompound technology effectiveness at up to 5 percent, as shown in Table 2 - 12 . In cremental cost increases associated with the addition of mechanical turbocompounding are significant, due to the complexity of the mechanical power transmission system required to connect the power turbine to the drivetrain. Such costs are estimated to be $ 1 , 049 inclusive of an RPE factor of 1.28 (i.e., $ 820 in direct manufacturing costs) in 2014 MY . 44 Electric turbocompound is another potential device, although it is still not as mature in terms of production compared to mechanic al turbocompound. An electric turbocompound sy stem uses a power turbine to drive an electrical generator which is used to power electric accessories or provide extra power to the engine. As noted in the 2010 NAS report, 45 electric turbocompound is a techn ology that fits particularly

well with a h ybrid electric powertrain for long - haul applications where regenerative braking opportunities are limited. The benefits of electric turbocompound and an electric h ybrid powertrain can be additive. TIAX used a ran ge of 4 to 5 percent for its estimates, which included the benefits of electric accessories. 46 The 2010 NAS report includes the benefit projections from three studies, as listed below. However, none of these sy stems have been demonstrated commercially . 47

 The NESCCAF/I CCT study modeled an electric turbocompound sy stem and estimated benefits at 4.2 percent, including electrification of accessories.  Caterpillar, Inc., as part of Department of Energy (DOE) funded work, modeled a s ys tem that showed 3 to 5 per cent improvement48

 John Deere investigated a sy stem (off - highway) that offered 10 percent improvement. Two - stage turbocharger technology has been used in production by Navistar and other manufacturers. Ford’s new developed 6.7L diesel engine features a tw in - compressor turbocharger. Higher boost with wider range of operations and higher efficiency can further enhance engine performance, thus fuel econom y. It is expected that this type of technology will continue to be improved by better matching with syst em and developing higher compressor and turbine efficiency . For this anal ys is, we have estimated the cost of turbocompounding at $ 875 ( 2009 $) based on the cost estimate noted above developed by I CF . This estimate includes a low complexity

I CM of 1. 15 . Th is cost is applicable in the 2017MY when engines placed in day cab and sleeper cab tractors are expected to add this technology . Flat - portion of the curve learning is considered applicable to this technology. For the more basic technology of improving the turbo efficiency , the agencies have estimated a cost of $ 18 ( 2009 $) including a low complexity

I CM of 1.1 5 . That estimate would be considered valid in the 2014MY and flat - portion of the learning curve would be applied going forward. Higher efficiency

air handling (air and exhaust transport) processes may also be produced in the 2014 and 2017 time frame. To maximize the efficiency of such processes, induction sy stems may

be improved by

manufacturing more efficientl y designed flow paths (including those associated with air cleaners, chambers, conduit, mass air flow sensors and intake manifolds) and b y designing such s ys tems for improved thermal control. Improved***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 35 turbocharging and air handling syst ems must include higher efficiency EGR sy stems and intercoolers that reduce frictional pressure loss while maximizing the ability to thermall y control induction air and EGR. EGR sy stems that often rel y upon an adverse pressure gradient (exhaust manifold pressures greater than intake manifold pressures) must be reconsidered and their adverse pressure gradients minimized. “Hy brid” EGR strategies which rely upon pressure gradients and EGR pumps may provide pathway s for improvement. Other components that of

fer opportunities for improved flow efficiency include cylinder heads, ports and exhaust manifolds to further reduce pumping losses. Variable air breathing s ys tems such as variable Valve Actuation may provide additional gains at different loads and speeds . The NESCCAF/I CCT study indicated up to 1.2% reduction could be achieved solely through improved EGR sy stems. 2.4.2.4 **Engine Parasitic and Friction Reduction** Engine parasitic and friction reduction is another key technical area that can be further improved i n production moving to 2014 and 2017 time frame. Reduced friction in bearings, valve trains, and the piston - to - liner interface will improve efficiency . Friction reduction opportunities in the engine valve train and at its roller/tappet interfaces exist for several production engines. The piston at its skirt/cylinder wall interface, wrist pin and oil ring/cylinder wall interface offers opportunities for friction reduction. Use of more advanced oil lubricant that could be available for production in the future can also play a key role in reducing friction. Any

friction reduction must be carefull y developed to avoid issues with durability or performance capability . Estimations of fuel consumption improvements due to reduced friction range from 0 percent to 2 percent. 49 The agencies determined the effectiveness of reduced friction and parasitic at 0 to 1.5 percent for 2014 model year and beyond. All fuel injection sy stem manufacturers are working hard to reduce parasitic loss due to high pressure pumps and common rail flow loss in the hope that those development would add up further fuel efficie ncy improvement. In cremental manufacturing costs increases associated with the reduction of parasitics and friction may

include those associated with an o ptimized, electric water pump, replacing a mechanically

driven water pump ($100). Additionally , an improved mechanical oil pump with more efficient relief mechanism and optimized hydrodynamic design may incur costs ($5). A fuel pump capable of delivering higher pressures and with efficient regulation may require improved materials and more elaborate regulating hardware ($5). Improved p istons with less friction generated at the skirt may require incrementally

more precision in finish machine operations ( $3). Finally , a more efficient, reduced friction valve train will require more precise machining processes and an increased parts count ($90). All costs were developed based on EPA’s engineering judgment and are the same as proposal. The costs presented here are considered to include a retail price equivalent factor of 1.28. Removing the 1.28 RPE factor from the above cost estimates and instead applying a low complexity

I CM of 1.1 5 results in the following costs: electric water pump, $ 91 ; improved mechanical oil pump, $ 5 , improved fuel pump, $ 5 ; improved pistons, $3; reduced friction valve train, $ 109 for LHDD engines and $ 82 for HHDD engines. All costs are in**Regulatory Impact Anal ysis** 

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2009 dollars and are applicable to the 2014MY. Flat - portion of the curve learning is con sidered applicable to all of these costs. 2.4.2.5 **Integrated Aftertreatment System** All manufacturers use diesel particulate filter (DPF) to reduce particulate matter (PM). All except Navistar rel y on SCR to reduce NOx emissions. Periodic regeneration to remove lo aded soot is required for all DPF. One way is to directly

inject the fuel into exhaust stream, called active regeneration, and a diesel oxidation catal ys t (DOC) or other device then oxidizes the fuel in the exhaust stream, providing the heat required for DPF regeneration and increasing the fuel consumption of the vehicle. The other method is to use NO 2 , called passive regeneration, to directly react with soot at much lower exhaust temperature than active regeneration. Use of advanced thermal management co uld be made in production to eliminate active regeneration, thus significantly improv ing fuel efficiency . Volvo has announced in 2009 that their 2010 DPF+SCR sy stem has eliminated active regeneration for on - highway

vehicles. 50 All other manufactur ers using SCR are working in the same direction, minimizing or eliminating active regeneration, thus improving fuel economy , providing efficiency improvements in the real world , although they are not reflected in the HD engine t est procedure . Higher SCR NO x conversion efficiency will allow higher engine - out NO x emissions (while still meeting the tailpipe NOx standard due to the aftertreatment) , and therefore, will give more room for engine sy stem optimization, while maintaining the same or even less diesel engine fluid (DEF) consumption. Advanced model based control on DEF usage and slip can further improve DEF consumption, and thus fuel efficiency . For those manufacturers that use SCR as their NO x reduction devices, properly integrated DPF and SCR sy stem is essential, which is not only able to improve emissions reductions, but also to improve fuel efficiency through more advancing canning design, thus minimizing pressure drop across the sy stem. Improvements in aftertreatment s ys tem efficiency should be technology

cost neutral, requiring no increases in precious metal loading or manufacturing expense, and only require additional development costs. The agencies have estimated the cost of additional improvements to the aftertreatement s ys tem at $25 for each percentage improvement in fuel consumption. This estimate is based on the agencies’ belief that this technology is, in fact, a very

cost effective approach to improving fuel consumption. As such, $25 per percent improvement is considered a reasonable cost. This cost would cover the engineering and test cell related costs necessary to develop and implement the improved control strategies that would allow for the improvem ents in fuel consumption. Importantly , the engineering work involved would be expected to result in cost savings to the aftertreatment and control hardware (lower platinum group metal (PGM) loadings, lower reductant dosing rates, etc.). Those savings are considered to be included in the $25 per percent estimate described here. Given the 4 percent expected improvement in fuel consumption results in an estimated cost of $ 117 ( 2009 $) for a 2014MY vehicle. This estimate includes a low complexity I CM of 1.1 5 and flat - portion of the curve learning from 2014 forward. Note that this cost is applied only to L HD diesel engines. The cost for this technology is considered separately

for MHD and H HD diesel***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 37 engines since the cost is considered largel y one of research and development which probabl y results in lower actual part cost. 2.4.2.6 **Electrification** Many accessories that are traditionally gear or belt driven by

a vehicle’s engine can be decoupled with the engine speed, so that those accessories can be tailored to a spec ific engine speed reducing parasitic loads, thus producing better efficiency . Examples include the engine water pump, oil pump, fuel injection pump, air compressor, power - steering pump, cooling fans, and the vehicle’s air - conditioning s ys tem. TIAX’s asse ssment of electrified accessories found that they could provide 0 to 3 percent improvement in fuel consumption. 51 The most tangible development toward production in 2017 time frame would be electric water and oil pumps. The agencies expect th at about 0.5 to 1.0 percent thermal efficiency improvement could be achieved with electrification of these two pumps. Costs for electrification are considered as part of the costs for improved water and oil pumps discussed in Section 2.4.2.4 . 2.4.2.7 **Waste Heat Recovery** Waste heat recovery

uses exhaust gas or other heat sources (such as EGR or coolant) from the primary

engine to develop additional powe r. Waste heat recovery sy stems have other names such as bottoming cycle or Rankine cycle. As described in the 2010 NAS report, a ty pical s ys tem consists of the following components: a feed pump to drive the working fluid from the condenser to the evaporat or (or boiler); the evaporator, which transfers waste heat energy from the primary

engine to the working fluid; an expander, which takes energy from the working fluid to make mechanical power; and a condenser that rejects unused heat energy from the bottom ing cycle working fluid before starting a new cycle. TIAX estimated a 12 kWh waste heat recovery sy stem would cost of $8,400 per truck. 52 Such costs include necessary power extraction unit and gearbox, heat exchangers and compressor. Alternativel y, the waste heat recovery

sy stem could produce electrical power. This t ype of system would need to be combined with hy bridization so that the e lectrical energy could be stored and used directly when needed to supplement engine power. The 2010 NAS report cited two studies related to waste heat recovery , as listed below. 53

 Cummins has shown a projected increase of thermal efficiency from 49.1 to 52 .9 percent (7.2 percent decrease in fuel consumption) using an organic Rankine cycle. 54 Cummins reports recovering 2.5 thermal efficiency points from the exhaust and 1.3 thermal efficiency points from the coolant and EGR stream.  The NESCCAF/I CCT report sh owed the effect of a steam bottoming cycle to reduce fuel consumption by up to 10 percent. The agencies’ assessment of this technology indicates that it currentl y exists only in the research phase and concluded that there is insufficient lead - time between now and 2017**Regulatory Impact Anal ysis** 

2 - 38

for this promising technology to be developed and applied generally to all heavy - dut y engines. TIAX noted in their report to the NAS committee that the engine improvements beyond 2015 model year included in their report are highl y uncertain, though they include Rankine cycle t ype waste heat recovery as applicable sometime between 2016 and 2020. C The Department of Energy , along with industry are both working to develop waste heat recovery s ys tems for heavy - dut y engines. At the Diesel Engine - Efficiency and Emissions Research (DEER) conference in 2010, Caterpillar presented details regarding their waste heat recovery s ys tems development effort. In their presentat ion, Caterpillar clearly noted that the work is a research project and therefore does not imply commercial viability . D At the same conference, Concepts NREC presented a status of exhaust energy recovery in heavy - dut y engines. The scope of Concepts NREC i ncluded the design and development of prototy pe parts. E Cummins, also in coordination with DOE, is also active in developing exhaust energy recovery s ys tems. Cummins made a presentation to the DEER conference in 2009 providing an update on their progress which highlighted opportunities to achieve a 10 percent engine efficiency improvement during their research, but indicated the need to focus their future development on areas with the highest recovery opportunities (such as EGR, exhaust, and charge air). F Cummins also indicated that future development would focus on reducing the high additional costs and sy stem complexity . Based upon the assessment of this information, the agencies did not include these technologies in determining the stringency of the f inal standards. However, we do believe the bottoming cycle approach represents a significant opportunity

to reduce fuel consumption and GHG emissions in the future. 2.4.2.8 **2014 Model Year HHD D**  **iesel Engine Package**  The agencies assessed the impact of technologi es over each of the SET modes to project an overall improvement in the 2014 model year. The agencies considered improvements in parasitic and friction losses through piston designs to reduce friction, improved lubrication, and improved water pump and oil pump designs to reduce parasitic losses. The aftertreatment improvements are available through additional improvements to lower backpressure of the sy stems and further optimization of the engine - out NOx levels. Improvements to the EGR sy stem and air flow through the intake and exhaust sy stems, along with turbochargers , can also produce engine efficiency improvements. Lastly , an increase in combustion pressures and controls can reduce fuel consumption of the engine. The projected impact of each set of these technologies is included in Table 2 - 7 . Based on the improvements listed in the table, the overall weighted reduction based on the SET mode weightings is projected at 3 percent . It should be pointed out that the improvements lis ted in

C TIAX Report (2009). Page 4 - 29. D Kruiswyk, R. “An Engine System Approach to Exhaust Waste Heat Recovery.” Presented at DOE DEER Conference on September 29, 2010. Last vie we d on May 11, 2011 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2010/wednesday/presentat ions/deer10_kruiswyk.pdf E Cooper, D,, N. Baines, N. Sharp. “Organic Rankine Cycle Turbine for Exhaust Energy Recovery in a Heavy Truck Engine.” Presented at the 2010 DEER Conference. Last viewed on May 11, 2011 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2010/wednesday/presentations/deer10_baines.pdf F Nelson, C. “Exhaust Energy Recovery.” Presented at the DOE DEER Conference on August 5, 2009. Last viewed on May 11, 2011 at http://www1.eere.energy. gov/vehiclesandfuels/pdfs/deer_2009/session5/deer09_nelson_1.pdf***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 39 Table 2 - 5 are not all additive, meaning that total benefits of individual technologies would not be equal to the benefits that are added up b y each technology numericall y.

**Table 2**  **- 7**  **: Projected Percent CO 2**  **Impact for SET Modes in 2014 Model Year** SET Mode Speed/%

Load Parasitics,

Friction Aftertreatment

Im provement Turbocharger,

Air Handling Sy stem Advanced

Controls, Com bustion, & Fuel inje c tion Im provements 1 Idle - 0.4 - 0.4 - 0.8 - 0.8 2 A, 100 - 0.8 - 1.0 - 0.8 - 0.4 3 B, 50 - 1.3 - 1.3 - 1.5 - 2.1 4 B, 75 - 0.8 - 0.8 - 0.8 - 0.8 5 A, 50 - 1.3 - 1.0 - 1.5 - 2.1 6 A, 75 - 0.6 - 1.0 - 1.3 - 1.0 7 A, 25 - 0.6 - 0.4 - 1.3 - 1.3 8 B, 100 - 0.8 - 1.0 - 0.8 - 0.4 9 B, 25 - 0.8 - 0.8 - 1.3 - 1.3 10 C, 100 - 0.8 - 1.0 - 0.8 - 0.4 11 C, 25 - 0.8 - 1.0 - 1.3 - 0.8 12 C, 75 - 1.0 - 1.0 - 1.0 - 0.4 13 C, 50 - 1.3 - 1.3 - 1.3 - 0.8 The agencies derived the HHD diesel engine FTP technology effectiveness for the 2014 model year based on a similar approach. Using the same technologies as discussed for the HHD diesel engine SET above, the agencies project the reductions at 3 percent. Itshould be pointed out that individual te chnology improvement is not additive to each other due to the interaction of technology to technology . The cost estimates for the complete H HD diesel engine packages are shown in Table 2 - 8 . **Table 2**  **- 8**  **Technology and Package Costs for H**  **HD D**  **iesel Engines (**  **2009 $)**  Technology 2014 2015 2016 2017 Cylinder Head $6 $6 $6 $6 Turbo efficiency $18 $18 $17 $17 EGR cooler $4 $4 $3 $3 Water pump $91 $89 $86 $84 Oil pump $5 $4 $4 $4 Fuel pump $5 $4 $4 $4**Regulatory Impact Anal ysis** 

2 - 40 Fuel rail $10 $10 $10 $9 Fuel injector $11 $11 $10 $10 Piston $3 $3 $3 $3 Engine Friction Reduction of Valvetrain $82 $80 $78 $76 Turbo - compounding (engines placed in combination tractors only) $0 $0 $0 $ 8 75 HHDD Total (vocational truck engines) $234 $228 $222 $ 216 HHDD Total ( combination tractors ) $234 $228 $222 $1,091 2.4.2.9 **2014 Model Year LHD/MHD Diesel**  **Engine Package** The agencies considered the same 2014 model year technology package developed for the HHD diesel engines for the LHD diesel and MHD diesel engines. The package includes parasitic and friction reduction, improved lubrication, aftertreatment improvements, EGR s ys tem and air flow improvements, and combustion pressure increase and controls to reduce fuel consumption of the engine. The agencies project that these improvements will produce a 5 percent reduction in fuel consumption and CO 2 . The cost estimates for the complete M HD diesel engines are shown in Table **2 -**  **9** . The cost estimates for the complete L HD diesel engines are shown in Table 2 - 10 . **Table 2**  **- 9**  **Technology and Package Costs for MHD Diesel**  **Engines ( 200**  **9 $)**  Technology 2014 2015 2016 2017 Cylinder Head $6 $6 $6 $6 Turbo efficiency $18 $18 $17 $17 EGR cooler $4 $4 $3 $3 Water pump $91 $89 $86 $84 Oil pump $5 $4 $4 $4 Fuel pump $5 $4 $4 $4 Fuel rail $10 $10 $10 $9 Fuel injector $11 $11 $10 $10 Piston $3 $3 $3 $3 Valve train friction reduction $82 $80 $78 $76 Turbo - compounding (engines placed in combination tractors only) $0 $0 $0 $ 8 75 MHDD Total (vocational truck engines) $234 $228 $222 $216 MHDD Total (combination tractors) $234 $228 $222 $1,091

**Table 2**  **- 10**  **Technology and Package Costs for L**  **HD D**  **iesel Engines (**  **2009 $)** 

Technology 2014 2015 2016 2017 Aftertreatment improvements $117 $114 $111 $108 Cylinder Head $11 $11 $10 $10 Turbo efficiency $18 $18 $17 $17 EGR cooler $4 $4 $3 $3***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 41 Water pump $91 $89 $86 $84 Oil pump $5 $4 $4 $4 Fuel pump $5 $4 $4 $4 Fuel rail $12 $12 $11 $11 Fuel injector $15 $14 $14 $13 Piston $3 $3 $3 $3 Valve train friction reduction $109 $106 $104 $101 LHDD Total $388 $378 $368 $358 2.4.2.10 **2014 Model Year Diesel Engine Standards** The agencies applied the 5 percent reduction for the LHDD/MHDD engines and the 3 percent reduction for the HHD diesel engines based on the projected technology package improvements in 2014 model year to the 2010 model year baseline performance included in Table 2 - 6 . The results are the final 2014 model year standards (and the equivalent voluntary fuel consumption standards) , as shown in Table 2 - 11 . **Table 2**  **- 11**  **: 2014 Model Year Final**  **Standards** LHDD - FTP MHDD -

FTP HHDD -

FTP MHDD SET HHDD -

SET CO 2 Emissions (g CO 2 /bhp - hr) 600 600 567 502 475 Fuel Consumption (gal/100 bhp hr) 5.89 5.89 5.57 4.93 4.67 2.4.2.11 **2017 Model Year HHDD Engine Package** The agencies assessed the impact of technologies over each of the SET modes to project an overall improvement in the 2017 model year. The agencies considered additional improvements in the technologies included in the 2014 model year package in addition to turbocompounding. The projected impact of each set of these technologies is included in Table 2 - 12 . Based on the improvements listed in the table, the overall weighted reduction based on the SET mode weightings is projected at 6 percent. Costs for 2017 are shown in 12 . **Table 2**  **- 12**  **: Projected CO 2**  **Imp rovements for SET Modes in 2017 Model Year**  SET Mode Speed/%

Load Turbocompounding

with clutch Parasitics,

Friction Aftertreatment

Im provement Turbocharger,

Air Handling Sy stem Advanced Controls,

Com bustion, & Fuel inje c tion Im provements 1 Idle 0.00 - 0.5 - 0.5 - 1.0 - 1.0 2 A, 100 - 4.50 - 1.0 - 1.3 - 1.0 - 0.5**Regulatory Impact Anal ysis** 

2 - 42

3 B, 50 - 2.50 - 1.5 - 1.5 - 1.8 - 2.5 4 B, 75 - 4.00 - 1.0 - 1.0 - 1.0 - 1.0 5 A, 50 - 2.00 - 1.5 - 1.3 - 1.8 - 2.5 6 A, 75 - 4.00 - 0.8 - 1.3 - 1.5 - 1.3 7 A, 25 0.00 - 0.8 - 0.5 - 1.5 - 1.5 8 B, 100 - 5.00 - 1.0 - 1.3 - 1.0 - 0.5 9 B, 25 0.00 - 1.0 - 1.0 - 1.5 - 1.5 10 C, 100 - 5.00 - 1.0 - 1.3 - 1.0 - 0.5 11 C, 25 0.00 - 1.0 - 1.3 - 1.5 - 1.0 12 C, 75 - 3.00 - 1.3 - 1.3 - 1.3 - 0.5 13 C, 50 - 2.00 - 1.5 - 1.5 - 1.5 - 1.0 The agencies derived the HHDD FTP technology package effectiveness for the 2017 model year based on a similar approach. However, the addition of turbocompounding shows a greater effectiveness on the SET cycle than the FTP cycle because of the steady state nature and amount of time spent at higher speeds and loads during the SET. Using the same technologies as discussed for the HHDD SET above, the agencies project the reductions at 5 percent for the FTP. Similar to Table 2 - 5 , individual technology in Table 2 - 10 is not additive to each other due to the interaction of technology to technology . 2.4.2.12 **2017 Model Year LHD/MHD Diesel**  **Engine Package** The agencies developed the 2017 model year LHD/MHD diesel engine package based on additional improvements in the technologies included in the 2014 model year package. The projected impact of these technologies provides an overall reduction of 9 percent over t he 2010 model year baseline. Costs for the 2017 model year are shown in **Table 2**  **- 9**  ( M HD) and Table 2 - 10 ( L HD). 2.4.2.13 **2017 Model Year Diesel Engine Standards** The agencies applied the 8.6 percent reduction for the LHD/MHD diesel engines and the 5 percent reduction for the HHD diesel engines using the F TP and a 6.1 percent reduction for HHD diesel engines using the SET based on the projected technology package improvements in 2017 model year to the 2010 model year baseline performance included in Table 2 - 6 . The results are the final 2014 model year standards (and the equivalent fuel consumption standards) , as shown in Table 2 - 13 . **Table 2**  **- 13**  **2017 Model Year Final**  **Standards** LHDD - FTP MHDD -

FTP HHDD -

FTP MHDD SET HHDD -

SET CO 2 Emissions (g CO 2 /bhp - hr) 576 576 555 487 460***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 43 Fuel Consumption (gal/100 bhp hr) 5.66 5.66 5.45 4.78 4.52 2.4.2.14 **Optional HD Diesel Engine Phase -**  **in Schedule** The agencies are finalizing an optional phase - in schedule for HD diesel engines which aligns with the timing of OBD requirements in 2013 and 2016 model years. The optional phase - in schedule requires that engines built in 2013 and 2016 model years achieve greater reductions than the engines built in those model years under the primary program, but less reduction 2014 and 2015 model year engine s. Overall, this phase - in schedule produces an equivalent CO 2 emissions and fuel consumption reduction as the primary program for the engines built in the 2013 through 201 7 model year timeframe as shown in Table 2 - 14 and Table 2 - 15 .

**Table 2**  **- 14**  **: Lifetim e CO**  **2 Emissions of Each Model Year Engine Installed in Tractors** 

HHD SET Engines MHD SET Engines Primary Phase - in Standard (g/bhp - hr) Optional

Phase - in Standard (g/bhp - hr) Difference in

Lifetime CO 2 Engine Emissions (MMT) Primary

Phase - in Standard (g/bhp - hr) Optional

Phase - in Standard (g/bhp - hr) Difference in

Lifetime CO 2 Engine Emissions (MMT) Baseline 490 490 -- 518 518 -- 2013 MY Engine 490 485 14 518 512 17 2014 MY Engine 475 485 - 28 502 512 - 28 2015 MY Engine 475 485 - 28 502 512 - 28 2016 MY Engine 475 460 42 502 487 42 2017 MY Engine 460 460 0 487 487 0 Net Reductions (MMT) 0 3 **Table 2**  **- 15**  **: Lifetim e CO**  **2 Emissions Reduction of Each Model Year Engine Installed in Vocational**  **Vehicles** HHD FTP LHD/MHD FTP Primary Phase - in Standard (g/bhp - hr) Optional

Phase - in Standard (g/bhp - hr) Difference in

Lifetime CO 2 Engine Emissions (MMT) Primary

Phase - in Standard (g/bhp - hr) Optional

Phase - in Standard (g/bhp - hr) Difference in

Lifetime CO 2 Engine Emissions (MMT) Baseline 584 584 -- 630 630 --**Regulatory Impact Anal ysis** 

2 - 44

2013 MY Engine 584 577 20 630 618 14 2014 MY Engine 567 577 - 28 600 618 - 22 2015 MY Engine 567 577 - 28 600 618 - 22 2016 MY Engine 567 555 34 600 576 29 2017 MY Engine 555 555 0 576 576 0 Net Reductions (MMT) - 3 0 

### 2.5 **Class 7 and**  **8 Day Cabs and Sleeper Cabs** The regulatory

category for Class 7 and 8 day

and sleeper cabs involves nine regulatory

subcategories. Class 7 Day

Cab with L ow Roof Class 7 Day

Cab with Mid Roof Class 7 Day

Cab with High Roof Class 8 Day

Cab with L ow Roof Class 8 Day

Cab with Mid Roof Class 8 Day

Cab with High Roof Class 8 Sleeper Cab with L ow Roof Class 8 Sleeper Cab with Mid Roof Class 8 Sleeper Cab with High Roof The regulatory

subcategories differentiate between tractor usages through using characteristics of the truck. The technologies considered to reduce fuel consumption and CO 2 emissions from tractors c an be developed for all of the subcategories. However, the typical usage pattern may

limit the penetration rate of the technology . For example, aerody namic improvements can reduce the fuel consumption and CO 2 emissions of a tractor at high speeds. However, this technology could be a detriment to fuel consumption if applied to a tractor travelling at low speeds. The agencies discuss technologies, penetration rates, and costs for each regulatory

subcategory

in the sections below.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 45 

### 2.5.1 **Aerodynamics** Up to 25 percent of the fuel consumed b y a line - haul truck traveling at highway speeds is used to overcome aerody namic drag forces, making aerody namic drag a significant contributor to a Class 7 or 8 tractor’s GHG emissions and fuel consumption. 55 Because aerody namic drag varies by

the square of the vehicle speed, small changes in the tractor aerodynamics can have significant impacts on GHG emissions and fuel efficiency of that vehicle. With much of their driving at highway speed, the benefits of reduced aerodyn amic drag for Class 7 or 8 tractors can be significant. 56 The common measure of aerodynamic efficiency is the coefficient of drag (Cd). The aerodynamic drag force (i.e., the force the vehicle must overcome due to air) is a function the Cd, the area presented to the wind (i.e., the projected area perpendicular to the direction of travel or frontal area), and the cube of the vehicle speed. Cd value s for today ’s fleet t ypically range from greater than 0.80 for a classic body tractor to approximately 0. 58 for tractors that incorporate a full package of widel y, commercially available aerodynamic features. 2.5.1.1 **Challenges of Tractor Aerodynamics** The aerodynamic efficiency of heav y - dut y vehicles has gained increasing interest in recent ye ars as fuel prices, comp etitive freight markets, and overall environmental awareness has focused owners and operators on getting as much useful work out of every gallon of diesel fuel as possible. While designers of heav y - duty vehicles and aftermarket products try to aerodynamic ally

streamline heavy - dut y vehicles, there are some challenges. Foremost is balancing the need to maximize the amount of freight that can be transported. For a tractor, this often means pulling a trailer that is as tall and as wide as motor safety laws p ermit, thereb y presenting a large, drag - inducing area perpendicular to the wind (i.e., projected frontal area). As a result, the tractor must also present a relativel y large projected frontal area to smoothly

manage the flow of air along the cab and trans ition it to trailer. In instances where the height of the cab is not properl y matched with that of trailer, aerodynamic drag can be significantly

increased by

creating large wakes (when the trailer is much shorter than the cab) or presenting a large non - aerodyn amic surface (when the trailer is taller than the cab). Aerodynamic design must also meet practical and safety needs such as providing for ph ys ical access and visual inspections of vehicle equipment. Because weight added to the vehicle impacts it s overall fuel efficiency and GHG emissions and, in some circumstances the amount of freight the vehicle can carry , aerodyn amic design and devices will sacrifice some benefit to overcoming their contribution to the vehicle weight. Aerodynamic designs and devices also must balance being as light and streamlined as possible with being durable enough to withstand the rigors a working, freight vehicle encounters while traveling or loading and unloading. Durability

can be a significant concern for cabs designe d for specialt y applications, such as “severe dut y” cabs that may operate on unimproved roads. In addition, absent mandatory

requirements, aerodynamic features for heav y - dut y vehicles must appeal to the owners and operators. Finally , because the behavior of airflow across the cab (and cab and trailer combination) is dependent upon the entire s ys tem, it is n o t possible to make inferences about the vehicle ’ s aerody namic performance based upon the performance of**Regulatory Impact Anal ysis** 

2 - 46

individual components. This can make it difficult to assess the benefit of adding (or subtracting) individual aerody namic features , and can discourage owners and operators from adopting aerodynamic technologies. 2.5.1.2 **Technology to Reduce Aerodynamic Drag** Addressing aerodynamic drag in Class 7 and 8 tractors requires considering the entire vehicle as a s ys tem to include the tractor and trailer. The overall shape can be optimized to minimize aerodynamic drag and, in fact, the tractor body must have at least a moderatel y aerodynamic shape (and its re latively smooth flow) to benefit from add - on aerodynamic components. Whether integrated into the shape of the tractor body or as an add - on component to a generall y aerodynamic tractor, there is a wide range of technologies available for Class 7 and 8 trac tors. Table 2 - 16 describes several of these potential aerody namic features and components .

**Table 2**  **- 16**  **: Technologies to Address Aerodynamic Drag** LOCAT ION ON CAB TECHNOLOGY

TYPE DESI GNED EFFECT Front Bumper, grill, hood,

windshield Minimize pressure created by front of vehicle moving ambient air to make way

for truck Side Fuel tank fairings Reduce surface area perpendicular to wind, minimize opportunity

to trap airflow, and smooth surface Top Roof fairings

(integrated) and wind vi sors (attached) Transition air to flow smoothly over trailer and minimize surface area perpendicular to the wind (for tractor and trailer) Rear Side extending gap

reducers Transition air to flow smoothly over trailer and reduce entrapment of air in gap be tween tractor and trailer Undercarriage Underbell y treatment Manage flow of air underneath tractor to reduce eddies and smoothly

transition flow to trailer Accessories Mirrors, signal horns,

exhaust Reducing surface area perpendicular to travel and minimizing complex shapes that may induce drag General Active air management Manage airflow b y actively directing or blowing air into reduce pressure drag General Advanced, passive air

management Manage airflow through passive aerodyn amic shapes or devices that keep flow attached to the vehicle (tractor and trailer) 2.5.1.3 **Aerodynamics in the Current Fleet** Aerodynamics in the Class 7 and 8 tractors fleet currentl y on the road ranges from trucks with few modern aerodynamic features , to those that address the major areas of aerodynamic drag , to tractors applying more advanced techniques. Because they operate at highway speeds less of the time, Class 7 and 8 tractors configured as day cabs (i.e., dedicated to regional routes) tend to have fewer aerodyn amic f eatures than cabs designed for line - haul applications. For tractors, it i s useful to consider aerodynamics in the current fleet in terms of***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 47 three packages: the “classic” truck body; the “conventional” truck body ; and the “SmartWay” truck body. “Clas sic” truck body: At the lower end of aerody namic performance are tractors that have a “classic” truck body . These truck bodies prioritize looks or special duty capabilities (e.g., clearance, durability on unimproved roads, and visual access to key vehicle components) and have remained relativel y unchanged since the 1970’s. Typical applications are logging, waste hauling, and some agricultural related uses. These trucks incorporate few, if any , aerody

namic features and several that detract from aerody nami cs including equipment such as bug deflectors, custom sunshades, air cleaners, b - pillar exhaust stacks, additional horns, lights and mirrors . “Conventional” truck body : The conventional, modern truck capitalizes on a generall y aerodyn amic shape and avoids classic features that increase drag. The conventional, modern truck body has removed extra equipment (e.g., bug deflectors, custom sunshades, additional signal horns, decorative lights), moved essential equipment out of the airflow (e.g., b - pillar exhaust stacks and air cleaners), and streamlined fixed - position, essential equipment (e.g., mirrors, steps, and safety lights). “SmartWay” truck body : The SmartWay aerodyn amic package builds off of the aerodynamic package required for a Class 8 sleeper cab high roof tractor to meet the SmartWay

design specifications and represents the top aerodyn amic package that is widely , commerciall y available. The SmartWay package is a fully aerodyn amic truck package which has an overa ll streamlined shape, removes drag - inducing features (i.e., those removed or moved in conventional, modern truck body), and adds components to reduce drag in the most significant areas on the tractor. This includes aerody namic features at the front to th e tractor (e.g., streamlined bumper, grill, and hood), sides (i.e., fuel tank fairings and streamlined mirrors), top (i.e., roof fairings), and rear (i.e., side extending gap reducers). Regional and line - haul applications often employ different approaches , such as removable, rooftop wind visors and fully

integrated, enclosed roof fairings, respectivel y, based upon their intended operation. More advanced aerodyn amic features are possible and are the focus of product development, pilot and testing projects , and, in some cases, product lines that have seen limited fleet adoption. Advanced aerodyn amic designs can further optimize the overall shape of the tractor and may

add other advanced aerodynamic features (e.g., underbody airflow treatment, down exhaust, and lowered ride height). Some advanced aerodynamic features, including those listed above, show promise but will likely need ongoing refinement as these technologies are tailored to specific applications and pay back periods are reduced. Fleets who se line - haul operations permit are currentl y testing and using some advanced aerodyn amic technologies today . 2.5.1.4 **Aerodynamic Bins** The agencies have characterized the ty pical aerody

namic performance (expressed as CdA ) and cost for select applications. To do so , it was necessary to represent the wide variet y**Regulatory Impact Anal ysis** 

2 - 48

of tractor aerodyn amic shapes

– which are a collection of the shapes of the multitude of component parts

– by

developing aerodynamic packages. These are called Bin s I, II, III, IV, and V. Bin I aerodynamic package: As described as a classic truck in section 2.4.1.3, these trucks incorporate few, if any , aerodyn amic features and several that detract from aerodynamics including equipment such as bug deflectors, custom sunshades, air cleaners, b pi llar exhaust stacks, additional horns, lights and mirrors may constitute a conventional vehicle. No cost for aerody namics is assumed for th is classic package. Bin II package: As described in section 2.4.1.3 as a conventional tractor this tra ctor capitalizes on a generally aerodynamic shape and avoids classic features that increase drag. No cost for aerodynamics is assumed for the conventional package since there has been no addition of additional body work and these moderate modifications to the tractor shape would not likely require the redesign of other components. Bin III package: Based upon the design requirements of EPA’s SmartWay Designated Tractors, this package has an overall streamlined shape, removes drag inducing feature s, and adds components (i.e., aerody namic mirrors, side fairings, aerodyn amic bumpers, and side extending gap reducers) to reduce drag in the most significant areas on the tractor. The Bin III aerodynamics package does add some incremental cost above the classic and conventional packages. Bin IV and Bin V packages: These packages include components similar to that found in the SmartWay

package but with additional aerody namic refinement. This can be a combination of more sophisticated shape and increased coverage of drag inducing elements. Where the Bin IV package represents a tractor using the most advanced aerody namics available today , the Bin V package is designed to represent aerody namics expected to be available in the near future. With more attention paid to aerodynamic performance than the conventi onal package, the Bin IV package is estimated to be slightl y more expensive than the Bin III package . As a representation of the future aerodynamics, the Bin V package is estimated as being 50 percent more expensive than the Bin IV package. The agencies developed the aerodyn amic drag area , CdA, bin values for the tractor categories based on coastdown testing conducted by EPA using the enhanced coastdown test procedures adopted for the final rule , as described in RIA Chapter 3.2.2.1.3 . The agencies supplemented these results with the CdA information described in the proposal, which was based on a previous EPA coastdown program using slightly different test procedures conducted for the proposal and literature survey s. Inaddition to the absolute CdA values, the agencies used the results of a wind tunnel evaluation of aerodyn amic components to help identify the appropriate width of bins . SAE 2006 - 01 - 3456 evaluated aerody namic components on a Class 8 high roof tractor and found that side extenders provide a CdA reduction of 0. 4 and tank and cab skirts pro vide a CdA reduction of 0. 3. 57 The agencies considered that the results from the earlier test program and literature are based on test procedures that are not identical to those adopted for this program, and therefore placed more weight on the results from the latest EPA coastdown test program.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 49 **Table 2**  **- 17**  **: Tractor Cd A**  **Values** Truck Expected Bin Source Cd A (m 2 ) Class 8 High Roof Sleeper Cab B - 3JM2 - 2H - TXCR Bin III EPA Test Program 6. 4 B - 3JM2 - 4N - TXCR Bin III - IV EPA Test Program 5.7 B - 3JM2 - 2K - TXCR Bin III EPA Test Program 6.3 C - 3JM2 - 1B - TXCR Bin III EPA Test Program 6. 2 C - 3JE2 - 1F - TXCR Bin II - III EPA Test Program 6.7 International ProStar Bin III - IV ATDS 58 5.3 - 5.5 Best Aero Truck Bin III DDC Spec Manager 6.0 Full Aero Bin III EPA PERE & MOVES Model 5.8 Roof Deflector Bin II EPA PERE & MOVES Model 6.4 International 9200i #1 Bin II TRC 7.0 International 9200i #2 Bin II NVFEL 6.9 CE - CERT Bin II EPA PERE & MOVES Model 7.3 No Aero Feature Bin I DDC Spec Manager 7.5 Baseline Truck Bin I McCallen, 1999 7.5 Class 8 Day Cab High Roof B - 3XM2 - 4M - TBCR Bin III EPA Test Program 6.7 International ProStar Bin III ATDS 5.7 Aero Features Bin III SAE 2005 - 01 - 3512 6.0 Roof Fairing Only Bin II SAE 2005 - 01 - 3512 6.5 Class 8 Sleeper Cab Low Roof C - 4XM7 - 1C - TGTW Bin II EPA Test Program 4.2 Class 8 Day Cab Low Roof International ProStar Bin II ATDS 4.7 Class 8 Sleeper Cab Mid Roof C - 3JM3 - 2K - TGTW Bin II EPA Test Program 5.0 For high roof combination tractor compliance determination, a manufacturer would use the aerodynamic results (CdA) determined through testing to establish the appropriate bin , as defined in Table 2 - 18 . The manufacturer would then input into GEM the Cd value specified for each bin. For example, if a manufacturer tests a Class 8 sleeper cab high roof tractor and the test produces a CdA value of 6. 2 , then the manufacturer would assign this tractor to the Class 8 Sleeper Cab High Roof Bin III. The manufacturer would then use the Cd value of 0.60 as the input to GEM.

**Table 2**  **- 18**  **: Aerodynam ic Input Definitions to GEM for High Roof**  **Tractors** CLASS 7 CLASS 8 Day Cab Day Cab Sleeper Cab**Regulatory Impact Anal ysis** 

2 - 50 High Roof High Roof High Roof Aerodynamic Test Results (CdA in m 2 ) Bin I ≥ 8.0 ≥ 8.0 ≥ 7.6 Bin II 7.1 - 7.9 7.1 - 7.9 6.7 - 7.5 Bin III 6.2 - 7.0 6.2 - 7.0 5.8 - 6.6 Bin IV 5.6 - 6.1 5.6 - 6.1 5.2 - 5.7 Bin V ≤ 5.5 ≤ 5.5 ≤ 5.1 Aerodynamic Input to GEM (Cd) Bin I 0.7 9 0.7 9 0.7 5 Bin II 0.7 2 0.7 2 0.6 8 Bin III 0.6 3 0.6 3 0. 60 Bin IV 0.5 6 0.5 6 0.5 2 Bin V 0.5 1 0.5 1 0.4 7 The CdA values in Table 2 - 19 **Error! Reference source not found. Error! Reference**  **source not found.** are based on testing using the enhanced coastdown test procedures adopted for the final rulemaking, which includes aerodynamic assessment of the low and mid roof tractors without a trailer. The removal of the trailer significantly reduces the CdA value o f mid roof tractors with tanker trailers because of the poor aerodynamic performance of the tanker trailer. The agencies developed the Cd input for each of the low and mid roof tractor bins to represent the Cd of the tractor, its frontal area, and the imp act of the Cd value due to the trailer such that the GEM value is representative of a tractor - trailer combination, as it is for the high roof tractors.

**Table 2**  **- 19**  **: Aerodynam ic Input Definitions to GEM for Low**  **and Mid Roof Tractors** CLASS 7 CLASS 8 Day Cab Day Cab Sleeper Cab Low Roof Mid Roof Low Roof Mid Roof Low Roof Mid Roof Aerodynamic Test Results (CdA in m 2 ) Bin I ≥ 5.1 ≥ 5.6 ≥ 5.1 ≥ 5.6 ≥ 5.1 ≥ 5.6 Bin II ≤ 5.0 ≤ 5.5 ≤ 5.0 ≤ 5.5 ≤ 5.0 ≤ 5.5 Aerodynamic Input to GEM (Cd) Bin I 0.77 0.87 0.77 0.87 0.77 0.87 Bin II 0.71 0.82 0.71 0.82 0.71 0.82 The agencies have conducted sensitivity analy sis of Cd values within GEM to determine the effectiveness of aerodyn amic technologies, as shown in Figure 2 - 1 . For a Class 8 sleeper cab with a high roof, the impact of moving from Bin II to Bin III is a 6.5 percent reduction in CO 2 emissions and fuel consumption.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 51 **Figure 2**  **- 1**  **: CO 2**  **Em issions Impact of Coefficient of Drag for a Class 8 Sleeper Cab, High Roof**  The agencies estimated the cost of the aerodynam ic packages based on IC F’s price estimates. 59 The agencies applied a 15 percent reduction to the prices to reflect savings due to a higher volume production which would be applicable to the tractor manufacturers. Althou gh technologies such as roof fairings may already be in widespread use today, the ICF study researched retail prices that a consumer would pay for the purchase of a single item in addition to researching possible saving s based on a large volume manufacturing . In addition, the agencies removed an RPE of 1.36 to obtain the direct manufacturer cost and then applied a low complexity

I CM of 1.18 or a medium comp lexity I CM of 1.30 (for Bin V ) to obtain the overall technology

costs included in Table 2 - 20 and Table 2 - 21 . In Table 2 - 22 and Table 2 - 23 the costs are shown including the expected penetration rates which range between 20 percent and 50 percent for most technologies shown. **Table 2**  **- 20**  **Estim ated Aerodynam** **ic Technology Costs for Class 7 & 8 Day Cabs for the 2014MY (200 9**  **$)** CLASS 7 DAYCAB CLASS 8 DAYCAB Low Roof High Roof Low Roof High Roof Bin I $0 $0 $0 $0 Bin II $0 $0 $0 $0 Bin III $1,126 $1,155 $1,126 $1,155 Bin IV $2,273 $2,303 $2,273 $2,303 Bin V $3,203 $3,245 $3,203 $3,245 **- 25%**  **- 20%**  **- 15%**  **- 10%**  **- 5%**  **0% 5%**  **10% 15%** 

**60 70**  **80 90**  **100 110**  **120**

**0.4 0.6**  **0.8 1**  **1.2 C** **O 2** **R e** **c u** **t i** **o n** **( %** **) W** **e i** **g h** **t e** **d C** **O 2** **( g** **/ t** **o n** **- m** **i l** **e )** 

**Cd** 

## Cl **as s**  **8 wi**  **th h**  **ig h**  **ro of s**  **leep er**  **CO2 S**  **en sitiv**  **it y**  **to C**  **d**

**We igh**  **ted C**  **O2 CO2**  **Re duc** **ti on** **Regulatory Impact Anal ysis** 

2 - 52

**Table 2**  **- 21**  **Estim ated Aerodynam** **ic Technology Costs for Class 8 Sleeper Cabs for the 2014M Y**  **( 2009**  **$)** LOW ROOF MID ROOF HI GH ROOF Bin I $0 $0 $0 Bin II $0 $0 $0 Bin III $1,374 $1,404 $1,560 Bin IV $2,601 $2,601 $2,675 Bin V $3,664 $3,664 $3,769 **Table 2**  **- 22**  **Estim ated Aerodynam** **ic Technology Costs for Class 7 & 8 Day Cabs**  **for the 2014MY Inclusive of Penetration Rates (**  **2009 $)**  CLASS 7 DAYCAB CLASS 8 DAYCAB Low Roof High Roof Low Roof High Roof Bin III $675 $693 $675 $693 Bin IV N/A $230 N/A $230 **Table 2**  **- 23**  **Estim ated Aerodynam** **ic Technology Costs for Class 8 Sleeper Cabs for the 2014MY Inclusive of Penetration Rates (**  **2009 $)**  LOW ROOF MID ROOF HI GH ROOF Bin II $962 $983 $1,092 Bin IV N/A N/A $535 

### 2.5.2 **Tires** Tire rolling resistance is defined as the energy consumed by

the tire per unit of distance traveled. Energy is consumed mainl y b y the deformation of the tires, known as hy steresis, but smaller losses are due to aerody namic drag and other friction forces b etween the tire and road surface and the tire and wheel rim. About 90 percent of a tire’s rolling resistance comes from h ysteresis. Collectively the forces that result in energy loss from the tires are referred to as rolling resistance. The share of tru ck energy required to overcome rolling resistance is estimated at nearl y 13 percent for Class 8 trucks . 60 Reducing a tire’s rolling resistance will reduce fuel consumption and lower emissions of CO 2 and other greenhouse gases. Low rolling resistance tire s are commerciall y available from most tire manufacturers. The EPA SmartWay program identified test methods and established criteria to designate certain tires as “low rolling resistance” for use in the program’s emissions tracking s ys tem, verification program, and SmartWay vehicle specifications. Below is a discussion of EPA’s approach to quantifying tire rolling resistance and the emission reductions associated with reduced rolling resistance, and a discussion of single wide tires, retread tires, and rep lacement tires. To measure a tire’s efficiency the vertical load supported by the tire must be factored because rolling resistance is a function of the load on a tire. EPA uses a tire’s rolling resistance coefficient (RRc ), which is measured as the rolling resistance force over vertical load (kg/metric ton). The RRc baseline for today ’s fleet is 7.8 kg/metric ton for the steer tire and 8.2 kg/metric ton for the drive tire, based on sales weighting of the top three***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 53 manufacturers by market share. These values are based on new tires, since rolling resistance decreases as the tread wears. Beginning in 2007, EPA began designating certain Class 8 sleeper - cab configurations as Certified SmartWay

Tractors. In order for a tractor to be designated as Certified SmartWay , the tractor must be equipped with verified low rolling resistance tires (either dual or single wide), among other criteria. In order to be verified as a low rolling resistance tire, a steer tire must have a RRc less than 6.6 kg/metric ton and a drive tire must have a RRc less than 7.0 kg/metric ton. SmartWay - verified low rolling resistance tires are the best performing tires available based on fuel efficiency . The SmartWay program expects to decrease the maximum allowable rolling r esistance coefficient by 10 percent between 2010 and 2014. As more low rolling resistance tires are sold, the baseline rolling resistance coefficient value will improve. Research indicates the contribution to overall vehicle fuel efficiency by tires is approximately

equal to the proportion of the vehicle weight on them . 61 On a fully loaded ty pical Class 8 long - haul truck (tractor and trailer), about 12.5 percent of the total tire energy loss attributed to rolling resistance is from the steer tires and about 42.5 percent is from the drive tires. When evaluating just the tractor, the proportionate amount of energy loss would be about 24 percent from the steer tires and 76 percent from the drive tires. A tire’s rolling resistance is a factor considered in the design of the tire , and is affected by the tread compound material, the architect ure of the casing, tread design and the tire manufacturing process. Differences in rolling resistance of up to 50 percent have been identified for tires designed to equip the same vehicle . 62 Itis estimated that 35 to 50 percent of a tire’s rolling resistance is from the tread and the other 50 to 65 percent is from the casing . 61 Tires with increa sed RRc values are likely designed for treadwear and not fuel efficiency . Research and testing have shown a 5 percent reduction of rolling resistance provides a fuel consumption reduction of 1 percent while maintaining similar traction and handling charact eristics. Bridgestone found a 5 percent improvement in rolling resistance will produce a 1.3 to 1.7 percent improvement in fuel econom y . 61 Assuming a truck achieves 6 miles per gallon and is driven 100,000 miles annually , a 1.5 percent improvement in fuel econom y results in a fuel consumption reduction of 1.48 percent, which is in line with EPA’s study . According to Bridgestone , 61 use of a fuel - efficient tire , compared to a non - fuel - efficient tire, will result in approximately a 12 percent improvement in fuel econom y at 55 mph, and 9 percent improvement in fuel econom y at 65 mph. To further demonstrate the correlation between rolling resistance and fuel economy , Michelin modeled vehicle fuel consumption using two drive cycles and various ro lling resistance values. One drive cycle incorporated several instances of stop and start that replicated driving a vehicle on a secondary road; the other drive cycle replicated driving on a highway at nearly uniform speed but with several elevation chang es. Simulations were performed using a base case and for rolling resistance reductions of 10 percent and 20 percent for both the secondary

roadway and highway

drive cycles. Michelin’s simulation modeling**Regulatory Impact Anal ysis** 

2 - 54

for the secondary

road drive cycle pr edicts a 1.8 percent and a 3.6 percent improvement in fuel econom y as a result of the 10 percent and 20 percent reduction in rolling resistance, respectivel y . 63 64 The simulation modeling for the highway drive cycle predicts a 2.6 percent and a 4.9 percent improvement in fuel econom y as a result of the 10 percent and 20 percent reduction in rolling resistance, respectively . 63 The modeling demonstrates less of a benefit from reduced rolling resistance when a vehicle is operated on secondary roadway s. Michelin’s modeling predicts an improvement in f uel econom y from a reduction in rolling resistance comparable to what Bridgestone demonstrated. A 5 percent reduction in rolling resistance results in a 1 percent improvement in fuel econom y. Proper tire inflation is critical to maintaining proper stres s distribution in the tire, which reduces heat loss and rolling resistance. Tires with reduced inflation pressure exhibit more sidewall flexing and tread shearing, therefore, have greater rolling resistance than a tire operating at its optimal inf lation pressure. Bridgestone tested the effect of inflation pressure and found a 2 percent variation in fuel consumption over a 40 psi range. 61 Generally , a 10 psi reduction in overall tire inflation results in about a 1 percent reduction in fuel economy . 65 To achieve the intended fuel efficiency benefits of low rolling resistance tires, it is critical that tires are maintained at the proper inflation pressure . Tire rolling resistance is only one of several performance criteria that affect tire selection. The characteristics of a tire also influence durability, traction control, vehicle handling and comfort. A si ngle performance parameter can easil y be enhanced, but an optimal balance of all the criteria must be maintained. Tire design requires balancing performance, since changes in design may change different performance characteristics in opposing direction . 66 Truck tires are most often axle - specific in relation to these different performance criteria . 67 The same tire on different axles or used in different applications can have a different rolling resistance value. Any changes to a tire would generally be accompanied with additional changes to suspension tuning and/or suspension design. The Center for Transportation Research at Argonne National Laboratory analyzed technology

options to support energy use projections. The Center estimated the incrementa l cost of low rolling resistance tires of $15 - $20 per tire . 84 The I CF report estimated the cost of low rolling resistance steer and drive tires to be $20 and $43 per tire, respectively . The NAS panel estimated $30 per tire. EPA and NHTSA project a c ost of $34 per tire or $ 68 per tractor ( 2009 $) for low rolling resistance steer tires (2 per truck) for both Class 7 and 8 tractors including a low complexity I CM of 1.18 , based on the cost estimate s provided by I CF for low rolling resistance tires . For lo w rolling resistance drive tires, the agencies estimate truck - based costs of $6 3 ( 2009 $) and $ 126 ( 2009 $) for Class 7 and 8 tractors, respectively , including a low complexity

I CM of 1.1 8 . The higher Class 8 reflects the assumption of one drive axle for Cl ass 7 tractors and two drive axles for Class 8 tractors. All costs are considered valid for the 2014MY and flat - portion of the curve learning would be considered appropriate for this technology . 2.5.2.1 **Single Wide Tires** Low rolling resistance tires are offered for dual assembly and as single wide tires. They are ty pically only used on the drive axle of a tractor. A single wide tire is a larger tire***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 55 with a lower profile. The common single wide sizes include 385/65R22.5, 425/65R22.5, 445/65R22.5, 435/50R22.5 and 445/50R22.5. Generall y, a single wide tire has less sidewall flexing compared to a dual assembly and therefore less hy steresis occurs. Compared to a dual tire assembly , single wide tires also produce less aerody namic resistance or drag. Single wide tires can contribute to improving a vehicle’s fuel efficiency through design as a low rolling resistance tire and/or through vehicle weight reduction. According to one study , the use of fuel efficient single wide tires can reduce rolling resistance b y 3.7 to 4.9 percent compared to the most equivalent dual tire . 68 An EPA study demonstrated an improvement in fuel econom y of 6 percent at 55 mph on the highway, 13 percent at 65 mph on the highway and 10 percent on a suburban loop 69 using single wide tires on the drive and trailer axles. EPA attributed the fuel econom y improvement to the reduction in rolling resistance and vehicle weight reduction from using single wide tires. In 2008 the Department of Energy

(DOE) compared the effect of different combinat ions of tires on the fuel efficiency

of Class 8 trucks. The data collected based on field testing indicates that trucks with tractors equipped with single wide tires on the drive axle experience better fuel econom y than trucks with tractors equipped with dual tires, independent of the ty pe of tire on the trailer . 70 This study

in particular indicated a 6.2 percent improvement in fuel econom y from single wide tires. There is also a weight savings associated with single wide tires compared to dual tires. Single wide tires can reduce a tractor and trailer’s weight b y as much as 1,000 lbs. when combined with aluminum wheels. Bulk haulers of gasoline and other liquids recognize the immediate advantage in carrying capacity provided by

the reduction in the w eight of tires and have led the transportation industry in retrofitting their tractors and trailers 71

. New generation single wide tires, which were first introduced in 2000, are designed to replace a set of dual tires on the drive and/or trailer positions. They are designed to be interchangeable with the dual tires without any change to the vehicle 72 . I f the vehicle does not have hub - piloted wheels, there may be a need to retrofit axle components 71

. Inaddition to consideration of hub / bearing / axle, other axle - end components may be affected by

use of single wide tires. To assure successful operation, suitable components should be fitted as re commended b y the vehicle manufacturer 73

. Current single wide tires are wider than earlier models and legal in all 50 states for a 5 - axle, 80,000 GVW truck 68 . Single wide tires meet the “inch - width” requirements nationwide, but are restricted in certain states up to 17,500 lbs. on a single axle at 500 lbs/inch width limit, and are not allowed on single axle positions on certain double and triple combination vehicles 72 . An inch - width law regulates the maximum load that a tire can carry as a function of the tire width. Ty picall y single wide tires are optimized for highway operation and not for city or on/off highway operation. However, newer single wide tires are being designed for better scrub resistance, which will allow an expansion of their use. The current market share of single wide tires in combination tractor applications is 5 percent and the potential market is all combination tractors. 68 New generation single wide tires represent an estimated 0.5 percent of the 17.5 million tires sold each ye ar in the U.S. 72

.**Regulatory Impact Anal ysis** 

2 - 56

The Center for Transportation Research at Argonne National Laboratory estimated incremental capital cost of single wide tires is $30 - $40 per tire . 84 IC F estimates the incremental price of low rolling resistance tires at $20 for drive tires and $43 for steer tires. 74 Based on the ICF estimates, the agencies project the incremental cost would be between $120 and $160 for four single wide tires replacing eight dual tires on a drive axle of a tractor . 2.5.2.2 **Tire Rolling Resistance** Based on the rolling resistance of today ’s tires and the rate of improvement that has been made in the recent past, the agencies are projecting the following tire rolling resistance performance for s etting the final tractor standards, as shown in Table 2 - 24 . **Table 2**  **- 24**  **Tire Rolling Resistance** Class 7 Class 8 Day Cab Day Cab Sleeper Cab Low/ Mid Roof High

Roof Low/Mid

Roof High

Roof Low

Roof Mid

Roof High

Roof **Steer Tires (Crr kg/metric ton)** Baseline 7.8 7.8 7.8 7.8 7.8 7.8 7.8 6.6 6.6 6.6 6.6 6.6 6.6 6.6 5.7 5.7 5.7 5.7 5.7 5.7 5.7 **Drive Tires (Crr kg/metric ton)** Baseline 8.2 8.2 8.2 8.2 8.2 8.2 8.2 7.0 7.0 7.0 7.0 7.0 7.0 7.0 6.0 6.0 6.0 6.0 6.0 6.0 6.0 Reducing the coefficient of rolling resistance from the baseline scenario of 7.2 kg/metric ton to 6.5 kg/metric ton reduces the CO 2 emissions and fuel consumption by 3.7 percent, as shown in Figure 2 - 2 below.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 57 **Figure 2**  **- 2**  **: Tire Rolling Resistance Impact on CO 2**  **Emissions of a Class 8 Sleeper Cab, High Roof** 

### 2.5.3 **Weight Reduction** Mass reduction encompasses a variet y of techniques ranging from improved design and better component integration to application of lighter and higher - strength materials. Mass reduction can be further compounded b y reductions in engine power and ancillary s ys tems (transm ission, steering, brakes, suspension, etc.). Although common on light - duty passenger vehicles for fuel economy and performance increases, mass reduction on heavy - duty vehicles is more complex due to the size and duty cycle of the vehicles. Reducing a vehic le’s mass decreases fuel consumption and GHG output by reducing the energy

demand needed to overcome forces resisting motion, and rolling resistance. Passenger vehicle manufacturers employ a sy stematic approach to mass reduction, where the net mass reduct ion is the addition of a direct component or sy stem mass reduction plus the additional mass reduction taken from indirect ancillary s ys tems and components, effectivel y compounding or obtaining a secondary mass reduction from a primary mass reduction. For example, use of a smaller, lighter engine with lower torque - output subsequently allows the use of a smaller, lighter - weight transmission and drive line components. Likewise, the compounded weight reductions of the body , engine and drivetrain reduce stress es on the suspension components, steering components, wheels, tires and brakes, allowing further reductions in the mass of these subsy stems. The reductions in unsprung masses such as **- 20%**  **- 15%**  **- 10%**  **- 5%**  **0% 5%**  **10% 15%** 

**60 70**  **80 90**  **100 110** 

**3 5**  **7 9**  **11 C** **O 2** **R e** **d u** **c t** **i o** **n (** **% )** **W e** **i g** **h t** **e d** **C O** **2 (** **g /** **t o** **n -** **m i** **l e** **)**

**Wei ght**  **ed C**  **rr (kg/**  **metri c**  **to n)** 



## Cl **as s**  **8 wi**  **th h**  **igh r**  **oof s leep**  **er CO2**  **S en**  **sitivity t**  **o Cr**  **r**

**Wei ght**  **ed C**  **O2 CO2**  **R ed**  **uc ti**  **on Regulatory Impact Anal** **ysis**

2 - 58

brakes, control arms, wheels and tires further reduce stresses in the su spension mounting points. This produces a compounding ripple effect of possible mass reductions. A fully loaded tractor - trailer combination can weigh up to 80,000 pounds or more . Reduction in overall vehicle weight could enable an increase in fre ight delivered on a ton mile basis. Practically , this enables more freight to be delivered per truck and improves freight transportation efficiency . In certain applications, heavy trucks are weight - limited (i.e. bulk cargo carriers), and reduced tractor an d trailer weight allows direct increases in the quantity of material that can be carried. Mass reduction can be accomplished by proven methods such as:  Smart Design: Computer aided engineering (CAE) tools can be used to better optimize load paths within structures b y reducing stresses and bending moments applied to structures. This allows better optimization of the sectional thicknesses of structural components to reduce mass while maintaining or improving the function of the component. Smart designs al so integrate separate parts in a manner that reduces mass by combining functions or the reduced use of separate fasteners.  Material Substitution: Substitution of lower density and/or higher strength materials into a design in a manner that preserves or i mproves the function of the component. This includes substitution of high - strength steels, aluminum, magnesium or composite materials for components currentl y fabricated from mild steel. Mass reduction through material substitution is currently broadl y a

pplied across both light - and heav y duty applications in all vehicle subs ys tems such as aluminum engine block, aluminum transmission housing, high - strength steel body structure, etc.  Reduced Powertrain Requirements: Reducing vehicle weight sufficientl y can allow for the use of a smaller, lighter and more efficient engine while maintaining or increasing work or cargo requirements. The subsequent reduced rotating mass ( e.g. , transmission, driveshafts/halfshafts, wheels and tires) via weight and/or size reduction of components are made possible by reduced torque output requirements. Reduced mass in heav y - duty vehicles can benefit fuel efficiency and CO 2 emissions in two way s. If a truck is running at its gross vehicle weight limit with high density freight, more freight can be carried on each trip, increasing the truck ’ s ton - miles per gallon. If the truck is carryi ng lower densit y freight and is below the GVW (or GCW) limit, the total vehicle mass is decreased, reducing rolling resistance and the power required to accelerate or climb grades. Mass reduction can be achieved b y making components with lighter materials (high strength steel, aluminum, composites) or b y eliminating components from the truck. A common component - elimination example is to use sin gle wide tires and aluminum rims to replace traditional dual tires and rims, eliminating eight steel rims and eight tires. Although many gains have been made to reduce truck mass, many of the features being added to modern trucks to benefit fuel econom y, s uch as additional aerody namic features or idle reduction s ys tems, have the effect of increasing truck weight , causing mass to stay relativel y constant. Material and manufacturing technologies can also play a significant role in vehicle***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 59 safet y b y reducing v ehicle weight, and in the improved performance of vehicle passive and active safet y s ys tems. Although new vehicle s ys tems, such as hy brid power trains, fuel cells and auxiliary

power will present complex packaging and weight issues, this will further incre ase the need for reductions in the weight of the body , chassis, and power train components in order to maintain vehicle functionality . EPA’s SmartWay

transport web page discusses how the truck fuel consumption increases with the weight of the combination tractor . Man y truck components are typicall y made of heavier material, such as steel. Heavier trucks require more fuel to accelerate and to climb hills, and may

reduce the amount of cargo that can be carried. 78 Every 10 percent drop in truck weight reduces fuel use about 5 percent. 79 Generally , an empt y truck makes up about one - third of the total weight of the truck. Using aluminum, metal alloys, metal matrix composites, and other lightweight components where appropriate can reduce empty truck weight (known a s “tare weight”), improve fuel efficiency , and reduce greenhouse gas emissions. As an example, trimming 3,000 pounds from a heav y truck (about 4 percent of its loaded weight) with lighter - weight components could improve fuel economy by up to 3 percent and trucks that employ more weight saving options would save more. In addition, in weight - sensitive applications, lightweight components can allow more cargo and increased productivity . Another report by the National Commission on Energy Policy estimates that a fuel econom y gain of 5.0 percent on certain applications could be achieved by vehicle mass reduction further illustrating the fuel econom y gains possible on heav y - duty applications 80 . A third report, estimated potential reductions in modal GHG emissions are 4.6 percent, however also states current light - weight materials are costly and are application and vehicle specific with further research and development for advanced materials are needed. 81 In support of the overall goal to cost - effectivel y enable tr ucks and other heavy vehicles to be more energy efficient and to use alternative fuels while reducing emissions, the 21st Century

Truck Partnership seeks to reduce parasitic energy losses due to the weight of heav y vehicles without reducing vehicle functio nality , durabilit y, reliability, or safet y, and to do so cost - effectivel y. Aggressive weight reduction goals vary according to the weight class of the vehicle with targets between 10 and 33 percent. 82 The weight targets for each vehicle class depend on the performance requirements and duty cycle. It is important to note that materials or technologies developed for a particular vehicle class are not necessaril y limited to that class. For example, materials developed for lightweight frames for pickup trucks, v ans, or SUVs will eventually

be used in Class 3 - 5 vehicles, and materials developed to meet the demanding performance requirements for Class 7 and 8 trucks will find application in smaller vehicles. Weight reduction must not in any way sacrifice the durabi lity , reliability , and performance of the vehicle. Attaining these goals by reducing inertial loading will yield substantial benefits such as increased fuel efficiency with concomitant reductions in emissions, increased available payload capacit y for some vehicles, reduced rolling resistance, and optimized safety

structures and aerodyn amic drag reduction sy stems. A 2009 NESC C AF report evaluated the potential to reduce fuel consumption and CO 2 emissions by

reducing weight from the baseline weight of 80,000 pounds. For the purpose of this calculation, the weight reduction could come either from carrying lighter freight or from a**Regulatory Impact Anal ysis** 

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reduc tion in the empty

weight of the truck. If the vehicle mass is reduced to 65,000 pounds, the fuel econom y improves to 5.9 MPG from 5.4 MPG. The fuel savings and CO 2 reduction on the baseline vehicle amount to about 0.5 percent per 1,000 pounds of mass reduction. 83 This result suggests that efforts to reduce the empty vehicle mass will have onl y a modest benefit on fuel econom y, fo r long haul routes. Argonne has also simulate d the effect of mass reduction on the fuel economy of heav y trucks through the National Renewable Energy Laboratory ’s Advanced Vehicle Simulator Model, ADVISOR. The Argonne simulations relied on a few driving schedules developed b y the West Virginia University (WVU) because there are no established driving schedules for heav y trucks . While simulating a Class 8 truck on the WVU Intercity Driving Schedule, a fuel econom y gain of 0.6 percent was observed for each 1 percent mass reduction from 65,000 lb to 58,000 lb 84 . The maximum speed during the simulation was 61 mph, and the average running speed (excluding stops) was 37.5 mph although most intercity Class 8 trucks average a much higher speed than 37.5 mph. Argonne assumed a 0.66 percent increase in fuel econom y for each 1 percent weight reduction and total possible estimated fuel econom y increases of 5

– 10 percent. While simulating a Class 6 truck on a WVU Suburban Driving Schedule, a fuel economy gain of 0.48 per cent was observed for each 1 percent mass reduction from 22,600 lb to 21,800 lb. The maximum speed during the simulation was 44.8 mph, and the average running speed was 21.5 mph. The potential fuel economy gains for medium trucks, both heavy - and light - , w ere capped at 5 percent since they are less likel y to be weight or volume limited, and so the use of expensive lightweight material would not be cost - effective. The principal barriers to overcome in reducing the weight of heav y vehicles are associated with the cost of lightweight materials, the difficulties in forming and manufacturing lightweight materials and structures, the cost of tooling for use in the manufacture of relativel y low - volume vehicles (when compared to automotive production volumes), and u ltimately , the extreme durability requirements of heav y vehicles. While light duty vehicles may

have a life span requirement of several hundred thousand miles, ty pical heav y - dut y commercial vehicles must last over 1 million miles with minimum maintenance, and often are used in secondary applications for many

more years. This requires high strength, lightweight materials that provide resistance to fatigue, corrosion, and can be economically repaired. Additionally , because of the limited production volumes an d the high levels of customization in the heavy - dut y market, tooling and manufacturing technologies that are used by the light - dut y automotive industry are often uneconomical for heavy vehicle manufacturers. Lightweight materials such as aluminum, titanium and carbon fiber composites provide the opportunity for significant weight reductions, but their material cost and difficult formi ng and manufacturing requirements make it difficult for them to compete with low - cost steels. In addition, although mass reduction is currentl y occurring on both vocational and line haul trucks, the addition of other s ys tems for fuel economy , performance o r comfort increases the truck mass offsetting the mass reduction that has already occurred, thus is not captured in the overall truck mass measurement. Most truck manufacturers offer lightweight tractor models that are 1,000 or more pounds lighter than com

parable models. Lighter - weight models combine different weight - saving options that may include: 85***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 61  Cast aluminum alloy wheels can save up to 40 pounds each for total savings of 400 pounds  Aluminum axle hubs can save over 120 pounds compared to ductile iron or steel  Centrifuse brake drums can save nearly 100 pounds compared to standard brake drums  Aluminum clutch housing can save 50 pounds compared to iron clutch housing  Composite front axle leaf springs can save 70 pounds compared to steel springs  Aluminum c ab frames can save hundreds of pounds compared to standard steel frames 2.5.3.1 **Derivation of Weight Technology Packages** The agencies see man y opportunities for weight reduction in tractors. However, the empty curb weight of tractors varies significantly today . Items as common as fuel tanks can vary between 50 and 300 gallons each for a given truck model. Information prov ided b y truck manufacturers indicates that there may be as much as a 5,000 to 17,000 pound difference in curb weight between the lightest and heaviest tractors within a regulatory subcategory

(such as Class 8 sleeper cab with a high roof). Because there i s such a large variation in the baseline weight among trucks that perform roughly similar functions with roughl y similar configurations, there is not an effective way to quantify

the exact CO 2 and fuel consumption benefit of mass reduction using GEM becaus e of the difficult y in establishing a baseline. However, if the weight reduction is limited to specific components on the tractor , then both the baseline and weight differentials for these are readily quantifiable and well - understood. In the NPRM, the a gencies proposed basing the standard stringency on a 400 pound weight reduction in Class 7 and 8 tractors through the substitution of single wide tires and light - weight wheels for dual tires and steel wheels. This approach was taken since there is a large variation in the baseline weight among trucks that perform roughl y similar functions with roughl y similar configurations . Because of this , the only effective way to quantify the exact CO 2 and fuel consumption benefit of mass reduction using GEM is to estimate baseline weights for specific components that can be replaced with light weight components . Li ght weight wheels are commerciall y available as are single wide tires and thus data on the weight reductions attributable to these two approaches is readil y available. The agencies received comments on this a pproach from Volvo, ATA, MEMA, Navistar, American Chemistry Council, the Auto Policy Center, Iron and Steel Institute, Arvin Meritor, Aluminum Association, and environmental groups and NGOs. Volvo and ATA stated that not all fleets can use single wide tir es and if this is the case the 400 pound weight reduction cannot be met. A number of additional commenters

– including American Chemistry

Council, The Auto Policy Center, Iron and Steel Institute, Aluminum Association, Arvin Meritor, MEMA, Navistar, Vo lvo, and environmental and nonprofit groups

– stated that manufacturers should be allowed to use additional light weight components in order to meet the tractor fuel consumption and CO 2 emissions standards. These groups stated that weight reductions shoul d not be limited to wheels and tires. Some of the groups asked that cab doors, cab sides and backs, cab underbodies, frame rails, cross members, clutch housings, transmission cases, axle differential carrier cases, brake drums, and other components b e allowed to be replaced with light - weight versions. Materials suggested for substitution included aluminum, light - weight aluminum, high strength steel, and plastic composites. The**Regulatory Impact Anal ysis** 

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American Iron and Steel Institute stated there are opportunities to red uce mass by

replacing mild steel

– which currently dominates the heavy - duty indus try

– with high strength steel. In addition, The American Auto Policy Center asked that manufacturers be allowed to use materials other than aluminum and high strength steel to comply with the regulations. DTNA asked that weight reduction due to engine downsizing be allowed to receive credit. Volvo requested that weight reductions due to changes in axle configuration be credited. They used the example of a customer selecti ng a 4 X 2 over a 6 X 4 axle tractor. In this case, they assert there would be a 1,000 pound weight savings from removing an axle. As proposed, man y of the material substitutions could have been considered as innovative technologies. In response to the a bove summarized comments, the agencies evaluated whether additional materials and components could be used for compliance with the tractor weight reduction through the primary program. The agencies reviewed comments and data received in response to the NP RM and additional studies cited by commenters. A summary of this review is provided in the following paragraphs. TIAX, in their report to the NAS, cited information from Alcoa identifying several mass reduction opportunities from material substitution in the tractor cab components which were similar to the ones identified by the Aluminum Association in their comments to this rulemaking. G TIAX included studies submitted by Alcoa showing the potential to reduce the weight of a tractor - trailer combination by 3,500 to 4,500 pounds. 86 Inaddition, the Department of Energy

has several projects underway to improve the freight efficiency of Class 8 trucks which provide relevant data: 87 DOE reviewed prospective lightweighting alternative materials and found that aluminum has a potential to reduce mass by 40 to 60 percent, which is in line with the estimates of mass reductions of various components provided b y Alcoa, and by the Aluminum A ssociation in their comments and as cited in the TIAX report. These combined studies, comments, and additional data provided information on specific components that could be replaced with aluminum components. With regard to high strength steel, the Iron and Steel Institute found that the use of high strength steel can reduce the weight of light duty trucks b y 25 percent. 88 Approximately 10 percent of this reduction results from material substitution and 15 percent from vehicle re design. While this study evaluated light - dut y trucks, the agencies believe that a similar reduction could be achieved in heav y - dut y trucks since the reductions from material substitution would likely

be similar in heavy - trucks as in light - trucks. U.S. DOE, in the report noted ab ove, identified opportunities to reduce mass by 10 percent through high strength steel. 89 This study was also for light - dut y vehicles. The agencies considered other materials such as plastic composites and magnesium substitutes but were not able to obtain weights for specific components made from these materials. We have therefore not included components made from these materials as possible

G TIAX. 2009. Pages 4 - 62 through 4 - 64.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 63 substitutes in the primary program, but they may be considered through the innovative technology

provisions. We may consider including these materials as part of the technology package on which standard stringency is predicated in a subsequent regulation if data becomes available. The agencies also evaluated the potential of plastic composites and magnesium component s to reduce heavy - duty vehicle weight. The agencies were not able to obtain weights for specific components made from these materials. Based on this analy sis, the agencies developed an expanded list of weight reduction opportunities for the final rulemaking, as listed in Table 2 - 25 . The list includes additional components, but not materials, from those proposed in the NPRM. For high strength steel, the weight reduction value is equal to 10 percent of the presumed baseline component weight, as the agencies used a conservative value based on the DOE report. We recognize that there may be additional potential for weight reduction in new high strength steel components which combine the reduction due to the material substitution along with improvements in redesign, as evidenced b y the studies done for light duty vehicles. In the development of the high strength steel component weights, we are onl y assuming a reduction from material substitution and no weight reduction from redesign, since we do not have any data specific to redesign of heav y - dut y components nor do we have a regulatory mechanism to differentiate between material substation and improved design. We are finalizing for wheels that both aluminum and light weight aluminum are eligible to be used as light - weight materials. Only aluminum can be used as a light - weight material for other components. The reason for this is data was available for light weight aluminum for wheels but was not available fo r other components. The agencies received comments on the proposal from the American Chemistry Council highlighting the role of plastics and composites in heavy- duty vehicles. As they stated, composites can be low density while having high strength and ar e currentl y used in applications such as oil pans and buses. The DOE mass reduction program demonstrated for heav y vehicles proof of concept designs for h yb rid composite doors with an overall mass savings of 40 percent; 30 percent mass reduction of a hood sy stem with carbon fiber sheet molding compound; 50 percent mass reduction from composite tie rods, trailing arms, and axles; and superplastically formed aluminum body panels. 90 While the agencies recognize these opportunities, we do not believe the techn ologies have advanced far enough to quantify the benefits of these materials because they are very dependent on the actual composite material. The agencies may consider such lightweighting opportunities in future actions, but are not including them as par t of the technology

package underl yi ng the tractor standard . Manufacturers which opt to pursue composite and plastic material substitutions may pursue credits through the innovative technology provisions. With regard to Volvo’s requ est that manufacturers be allowed to receive credit for trucks with fewer axles, the agencies recognize that truck options exist today which have less mass than other options. However, we believe the decisions to add or subtract such components will be made based on the intended use of the vehicle and not based on a**Regulatory Impact Anal ysis** 

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crediting for the mass difference in our compliance program. It is not our intention to create a tradeoff between the right truck to serve a need (e.g. one with more or fewer axles) and compliance with our final standards. Therefore, we are not including provisions to credit (or penalize) vehicle performance based on the subtraction (or addition) of specific vehicle components configuration contain ing dual tires with steel wheels. The agencies continue to believe that the 400 pound weight target is appropriate for setting the final combination tractor CO 2 emissions and fuel consumption standards. The agencies agree with the commenter that 400 pounds of weight reduction without the use of single wide tires may

not be achievable for all tractor configurations. The agencies have extended the list of weight reduction components in order to provide the manufacturers with additional means to comply with the combination tractors and to furth er encourage reductions in vehicle weight. The agencies considered increasing the target value beyond 400 pounds given the additional reduction potential identified in the expanded technology list; however, lacking information on the capacity for the indu stry to change to these light weight components across the board b y the 2014 model year , we have decided to maintain the 400 pound target. The agencies intend to continue to study the potential for additional weight reductions in our future work consideri ng a second phase of truck fuel efficiency and GHG regulations. **Table 2**  **- 25**  **: Weight Reductions** WEI GHT REDUCTION TEC HNOLOGY WEI GHT REDUCTION ( LB PER TIRE/WHEEL) Single Wide Drive Tire with .. . Steel Wheel 84

Aluminum Wheel 139 Li ght Weight Aluminum Wheel 147 Steer Tire or Dual Wide Drive Tire with

... High Strength Steel

Wheel 8 Aluminum Wheel 21 Li ght Weight Aluminum Wheel 30 Weight Reduction Technolog ies AluminumWeight Reduction (lb.) High Strength Steel

Weight Reduction (lb.) Door 20 6 Roof 60 18 Cab rear wall 49 16 Cab floor 56 18 Hood Support Structure 15 3 Fairing Support Structure 35 6 Instrument Panel Support Structure 5 1 Brake Drums

– Drive (4) 140 11 Brake Drums

– Non Drive (2) 60 8 Frame Rails 440 87 Crossmember - Cab 15 5***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 65 Crossmember

– Suspension 25 6 Crossmember

– Non Suspension (3) 15 5 Fifth Wheel 100 25 Radiator Support 20 6 Fuel Tank Support Structure 40 12 Steps 35 6 Bumper 33 10 Shackles 10 3 Front Axle 60 15 Suspension Brackets, Hangers 100 30 Transmission Case 50 12 Clutch Housing 40 10 Drive Axle Hubs (8) 160 4 Non Drive Front Hubs (2) 40 5 Driveshaft 20 5 Transmission/Clutch Shift Levers 20 4 EPA and NHTSA are specifying the baseline vehicle weight for each regulatory vehicle subcategory

(including the tires, wheels, frame, and cab components) in GEM in aggregate based on weight of vehicles used in EPA’s aerody namic test program, but allow manu facturers to specify

the use of light - weight components. GEM then quantifies the weight reductions based on the pre - determined weight of the baseline component minus the pre - determined weight of the component made from light - weight material. Manufacturer s cannot specify

the weight of the light - weight component themselves, only the material used in the substitute component. The agencies assume the baseline wheel and tire configuration contains dual tires with steel wheels, along with steel frame and cab c omponents, because these represent the vast majority of new vehicle configurations today . The weight reduction due to replacement of components with light weight versions will be reflected partiall y in the payload tons and partially in reducing the ove rall weight of the vehicle run in GEM. The specified payload in GEM will be set to the prescribed payload plus one third of the weight reduction amount to recognize that approximately one third of the truck miles are travelled at maximum payload, as discu ssed below in the payload discussion. The other two thirds of the weight reduction will be subtracted from the overall vehicle weight prescribed in GEM. The impact of vehicle mass reductions on a Class 8 combination tractor modeled in GEM over the compos ite test cycle is shown in Figure 2 - 3 . The figure depicts both the weighted CO 2 results and the percent CO 2 reduction for a sample Class 8 combination tractor at vari ous weight reduction levels .**Regulatory Impact Anal ysis** 

2 - 66 **Figure 2**  **- 3**  **: Weight Reduction Impact on Combination Tractor** The agencies have estimated costs for the wheel and tire weight reduction technologies. Those costs are shown in Table 2 - 26 . The costs shown include a low complexity

I CM of 1.1 8 and flat - portion of the curve learning would be considered appropriate for these technologies. **Table 2**  **- 26**  **Estim ated Weight Reduction Technology Costs for Class 7 & 8 Tractors for the 2014MY**  **( 2009**  **$)** CLASS 7 TRACTORS CLASS 8 TRACTORS Single Wide Tire (per tractor) $336 $672 Aluminum Steer Wheel $546 $546 Aluminum Wheels - dual $1,637 $2,727 Aluminum Wheel

– Single wide $654 $1,308 W eight reduction s will be reflected in GEM in two parts. The reason for evaluating the impact of weight reduction in this way is because weight reduction is most effective in trucks that are at maximum payload. Weight reduction in tr ucks at maximum payload allows the truck to carry

additional freight. This additional freight reduces the fuel consumption on a ton - mile basis to a much greater extent than does reducing the weight of the tr uck alone. The agencies estimated that one tire of truck miles are travelled at maximum payload. For this assessment, the agencies assumed the o verall mass of the vehicle will be reduced b y an amount equal to two - thirds of the mass reduction to account for the vehicles miles which are travelled at less than maximum payload. Second , the specified payload will be increased by the weight reduction amount discounted by two thirds to recognize that approximately one third of the truck miles are travelled at maximum payload. **0.0% 0.2%**  **0.4% 0.6%**  **0.8% 1.0%** 

**88.6 88.8**  **89.0 89.2**  **89.4 89.6** 

**0 200**  **400 600**  **800 1000** **C O** **2 R** **E d** **u c** **t i** **o n** **( %** **) W** **e i** **g h** **t e** **d C** **O 2** **( g** **/ t** **o n** **- m** **i l** **e )** 

**Wei ght**  **R ed**  **uc ed**  **( lb)** 



## We **ig ht**  **R ed**  **uct io**  **n I**  **mp ac**  **t on**  **Cl as**  **s 8**  **Com bi**  **na tio**  **n Tr**  **uck**

**Wei ght**  **ed C**  **O2 CO2**  **Re duc**  **ti on** ***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 67 

### 2.5.4 **Extended Idle** Class 8 heav y - dut y diesel truck extended engine idling expends significant amounts of fuel in the United States. Department of Transportation regulations require a certain amount of rest for a corresponding period of driving hours , as discussed in Chapter 1 . Extended idle occurs when Class 8 long haul drivers rest in the sleeper/cab compartment during rest periods as drivers find it more convenient and economical to rest in the truck cab itself. In man y cases it is the only

option available. During this rest period a driver will generall y idle the truck in order to provide heating or cooling or run on - board appliances. During rest periods the truck’s main propulsion engine is running but not engaged in gear and it remains in a stationary position. In some cases the engine can idle in excess of 10 hours. During this period of time, fuel consumption will ge nerall y average 0.8 gallons per hour. 91 Average overnight fuel usage would exceed 8 gallons in this example. When multiplied by the number of long haul trucks without idle control technology that operate on national highways on a daily basis , the number of gallons consumed b y extended idling would exceed 3 million gallons per day . Fortunately , a number of alternatives (idling reduction technologies) are available to alleviate this situation. 2.5.4.1 **Idle Control Technologies** Idle reduction technologies in general utilize an alternative energy source in place of operating the main engine. By using these devices the truck driver can obtain needed power for services and appliances without running the engine. A number of these devices attach to the truck providing he at, air conditioning, or electrical power for microwave oven s , televisions, etc. The idle control technologies (along with their ty pical hourly

fuel rate) available today include the following: 92

 Auxiliary

Power Unit (APU) powers the truck’s heating, cooling, and electrical sy stem. The fuel use of an APU is ty pically 0.2 gallons per hour .  Fuel Operated Heater (FOH) provides heating services to the truck through small diesel fired heaters. The fuel use is typicall y 0.04 ga llons per hour.  Battery

Air Conditioning Sy stems (BAC) provides cooling to the truck.  Thermal Storage S ys tems provide cooling to trucks. Another alternative involves electrified parking spaces (EPS) , with or without modification to the truck. An EPS sy ste m operates independently of the truck’s engine and allows the truck engine to be turned off as the EPS sy stem supplies heating, cooling, and electrical power. The EPS sy stem provides off - board electrical power to operate either:**Regulatory Impact Anal ysis** 

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1. A single s ys tem electrification which requires no on - board equipment b y providing an independent heating, cooling, and electrical power s ys tem, or 2. A dual sy stem which allows driver to plug in on - board equipment . In the first case , power is provided to stationary equipment that is temporarily attached to the truck. In the second, the truck is modified to accept power from the electrical grid to operate on - board truck equipment. The retail price of idle reduction sy stems varies depending on the level of sophistication . F or example , on - board technologies such as APUs can retail for over $7,000 while options such as EPS require negligible up - front costs for equipment for the truck itself, but will accrue fees with usage. 5 2.5.4.2 **CO 2**  **Emissions and Fuel Consumption**  **Idle Reduction Benefit** CO 2 emissions and fuel consumption during extended idling are significant contributor s to emissions and fuel consumption from Class 8 sleeper cabs. The federal test procedure does evaluate idle emissions and fuel consumption as part of the drive cycle and related emissions measurement. However, long duration extended idle emissions and fuel consumption are not fully represented during the prescribed test cycle. To address the fact that real - world fuel and emissions savings can occur with idle reduction technologies that cannot be reflected on the test cycle, the agencies are adopting a credit mechanism for manufacturers who provide for idle control using an automatic engine shutdown (AES) sy stem on the tractor. Th is credit recognizes the CO 2 reductions and fuel consumption savings attributed to idle control sy stems and allow s truck manufacturers flexibility in prod uct design and performance capabilities , compared to an alternative where the agencies would allow credits for specific idle control technologies . For a manufacturer to qualify for the credit, the agencies are requiring that a truck have an automatic engine shutdown sy stem enabled at time of purchase that shuts off the engine after five minutes of idling when it is in a parked position. To provide power while the engine is off, truck owners can obtain additional verified idle reduction technologies ( IRT) on a new truck at the time of purchase from the manufacturer or install verified technology after purchase. This approach also allows for operational strategies such as electrified parking spaces, team drivers, and overnights spent in hotels to achie ve real - world reduction s of idling emissions and fuel consumption, while being assured through a tie - back to a verifiable technology - engine shut down . With an AES sy stem, it is reasonable to assume that one or several of the idle control technologies described above will also be employed in order to allow the driver to rest in the truck during the mandated rest periods . The i dle reduction credit value i s based on the CO 2 emission and fuel consumption reduction from the technology when compared to main engine idling, as shown in Table 2 - 27 . The agencies assume that the main engine consumes approximately 0.8 gal/hr during idling. 93 ACEE E argued that the agencies should us e a fuel consumption rate of 0.47 gallon/hour for main en gine idling based on a paper written by Kahn. MEMA argued that the agencies should use a main engine idling fuel consumption rate of 0.87 gal/hr , which is the midpoint of a DOE calculator r eport ing fuel consumption rates from 0.64 to 1.15 gal/hr at idling conditions , and between 800 and 1200 rpm with the air conditioning on and off , respectivel y . Having reviewed these comments and the sources provided, the agencies continue to believe***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 69 that 0.8 gal/hr is the best estimate for a main engine idling fuel cons umption rate. In the Kahn paper cited b y ACEEE, the author states that while idling fuel consumption is 0.47 gal/hr on average for 600 rpm, CO 2 emissions increase by 25 percent with A/C on at 600 rpm, and increase b y 165 percent between 600 rpm and 1 , 100 rpm with A/C on. 94 Inaddition, the presentation b y Gaines , which is also mentioned , provide s idling fue l consumption rates ranging between 0.6 and 1.2 gal lon/hour. Drivers ty picall y idle at speeds greater than 600 rpm for heating or cooling, to provide power for accessories such as interior lights , and protect the engine from damage . Finally , both the Gaines study and the NAS report cited in the RIA use 0.8 gal lon/hour. Therefore, the agencies are adopting a main engine idle fuel consumption rate of 0.8 gallon/hour. Using a factor of 10,180 grams of CO 2 per gallon of diesel fuel, the CO 2 emissions fro m the main engine at idle is 8,144 g per hour. The agencies assumed the average Class 8 sleeper cab spends 1,800 hours in extended idle per year to determine the idling emissions per year. 95 MEMA recommend ed using 2,500 hours per ye ar for APU operation , citing the SmartWay website which uses 2,400 hours per ye ar (8 hours per day

and 300 day s per year) , and an Argonne study which assumed 7 hours per day and 303 day s per year, which equals 2,121 hours per year. MEMA also cited the FMCSA 2010 driver guidelines , which reduce the number of hours driven per day by one to two hours, which would lead to 2,650 to 2,900 hours per ye ar in total . The agencies reviewed these and other studies to quantify idling operation. The 2010 NAS study assumes between 1,500 and 2,400 idling hours per year. 96 Gaines uses 1,800 hours per ye ar. 97 Brodrick, et al. assumes 1,818 hours per year (6 hours per day for 303 day s per year) based on an Argonne study and Freightliner fleet customers. 98 An EPA technical paper states between 1,500 and 2,400 hours per year. 99 Kahn uses 1,830 hours as the base line extended idle case. 100 Based on the literature, the agencies are finalizing as proposed the use of 1,800 hours per ye ar as reasonabl y reflecting the available range of information . The agencies then assumed the average Class 8 sleeper cab travels 125,000 miles per ye ar (500 miles per day

and 250 day s per year) and carries 19 tons of payload (the standardized payload finalized for Class 8 tractors) to calculate the baseline emissions as 6.2 grams of CO 2 per ton - mile. The agencies proposed that the fuel consumption of a diesel fueled APU would be used to quantify the fuel consumption and CO 2 emissions reduction of engines using an AES. The agencies assumed APUs consume approximately 0.2 gallon of diesel fuel per hour. 101 ACEEE argued that the agencies should use a fuel rate of 0.23 ga l/hour for the APU (based on Gaines presentation). In response, the agencies reviewed the NAS study which lists 12 APUs and their associated fuel consumption, which ranged between 0.04 and 0.4 0 gal/hour. The average in the NAS report is 0.2 gal/hour. 102 Due to the range of fuel consumption of APUs and the pre cision of the available test information, the agencies are finalizing as proposed an APU fuel consumption of 0.2 gal/hr , which is consistent with ACEEE’s comment . The CO 2 emissions from the APU equate to 1.5 grams per ton - mile. Therefore, the agencies are finalizing an idle reduction credit of 5 g CO 2 per ton - mile (0.5 gal/1,000 ton mile) which represents the difference in emissions and fuel consumption between the main**Regulatory Impact Anal ysis** 

2 - 70

e ngine idling and operation of an APU. Credits are based on the requirement that all Class 8 sleeper cabs shall be equipped with an automatic engine shut down . The credit reflects a technology ’s fuel consumption in conjunction with a shut down . **Table 2**  **- 27**  **: Idle Emissions Reduction**  **Calculation**

The agencies are finalizing an approach that allows manufacturers to provide an AES with a limited life to address concerns about resale value of trucks with an automatic engine shutoff. EMA/TMA specificall y requested that manufacturers be allowed to program an “expiration date”, based on time or mileage , into the AES feature, after which it could be reprogrammed. EMA/TMA argued that the extended idle reduction technologies must have features that can be modified for unfore seen uses in the secondary market. EMA/TMA also requested that GEM be updated to accommodate an expiration date and its associated impact of emission reductions. As part of this provision, the agencies will discount the value of the AES based on the number of miles in which it is preset relative to the lifetime of the tractor. The agencies calculated the lifetime miles of a combination tractor based on EPA’s MOVES model as 1,258,788 miles. The lifetime value is weighted to take into account the survival rate of heav y - dut y trucks, as shown in Table 2 - 28 .

**Table 2**  **- 28**  **: Lifetim**  **e Miles of 2015 MY Com** **bination Tractor** AGE COMBINATION TRACTOR VMT

PER YEAR 1 130,832 2 119,001 3 108,164 4 97,441 5 87,476 6 78,930 7 70,940 8 63,474 9 56,865 10 50,887 11 45,567 12 40,906 13 36,679 14 32,876 Idle Fuel Consumption (gal/hour) Idle CO 2

emissions per hour Idle

Hours per Year Idle CO 2 Emission per year (grams) Miles

Per Year Payload (tons) GHG Emissions D ue to Idling (g/ton mile) GHG

Reduction (g/ton mile) Fuel

Consumption Reduction (gal/ 1 ,0 00 ton - mile) Baseline 0.8 8,144 1,800 14,659,200 125,000 19 6.2 Idle Reduction Technology 0.2 2,036 1,800 3,664,800 125,000 19 1.5 5 0.5***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 71 15 29,406 16 26,408 17 23,657 18 21,230 19 18,977 20 17,013 21 15,221 22 13,679 23 12,232 24 10,927 25 9,764 26 8,718 27 7,785 28 6,966 29 6,233 30 5,562 The equation to derive the GEM input for IRT for sy stems with an AES expiration is shown in Equation 2 - 1 . **Equation 2**  **- 1**  **: Discounted IRT Equation for GEM Input**  GEM IRT Input = 5 g CO 2 /ton - mile * (miles at expiration / 1, 259 , 000 miles) 2.5.4.3 **Automatic Engine Shutdown Overrides** The agencies explained in the proposal that we were unaware of reasons why extended idle reduction technologies could not be applied to all tractors with sleeper cabs, but welcomed comments. The agencies received comments from ATA, DTNA, EMA/TMA, Cummins, TRALA and CARB , generally in support of the AES technology but with strong concerns that override capabilities must be allowed to address safety, emergency, servicing and maintenance issues. Upon consideration of these comments, the agencies are adopting si x ov erride provisions . The California Air Resources Board (CARB) currently has an anti idling rule for all medium - and heav y - duty vehicles , with several override provisions. 103 The agencies find that four of CARB’s override provisions are appropriate for the scope of this program – addressing long - term idling of Class 8 sleeper cab tractors - and are adopting similar provisions in this final HD National Program. CARB’s anti - idl ing rule allows overrides for four of the situations named below: regeneration , engine/vehicle servicing , low coolant temperature and PTO operation. In addition, the agencies are adopting two override provisions that are not from CARB’s rule : low battery state - of - charge and extreme ambient temperatures; which were requested by several of the industry commenters listed above . T he stringency

of the final HD rules is predicated on a ll Cl ass 8 sleeper cab tractors employing AES to reduce long - term idling of the main engine during mandated driver rest periods. The amount of reduc ed emissions and fuel savings by employing this IRT is**Regulatory Impact Anal ysis** 

2 - 72

described above, and presumes a default value based on the use of a diesel APU in lieu of main engine idle. Whi le not mandating an y IRT beyon d the AES, the agencies anticipate an appropriate device or s ys tem would ty picall y be installed as needed to provide an alternate source of power while the main engine is off, for the comfort and safety of the driver during mandated rest periods . As described above and in the preamble in Section III.A.2, truck manufacturers may obtain the AES credit without identifying an alternate power source. Having considered this issue further in response to comments, the agencies believ e that the override provisions adopted in the final rules are necessary because they prevent undesirable engine operation , provide for service, maintenance or inspections, and protect driver safety should a tractor not have an alternate power source, or an adequate one for extreme conditions. Two of the final override provisions requested b y ATA, DTNA and EMA/TMA allow the automatic shutdown to be delayed for reasons related to engine servicing: when an exhaust emission control device un dergoes regeneration, and when the engine /vehicle is undergoing servicing , maintenance or inspection . It is expected that the duration of each instance of these events would ty picall y range from 30 to 60 minutes. It is not known whether or how often a re generation event would occur during a driver rest period, as the frequency of these events depends on driving patterns and manufacturer settings. Nonetheless, regeneration and engine/vehicle servicing are both activities during which the agencies recognize that an automatic shutdown would be undesirable. In response to comments received from EMA/TMA the agencies are adopting an AES override in the case that the vehicle’s main battery state - of - charge is too low to restart the engine. In the event that the battery is drained excessively

while the engine is off, and a backup battery

is not functioning, the agencies recognize that allowing override of the AES may assist a driver in such an emergency situation. A main engine may be unable to start if its batte ry state of charge falls below a specified threshold . The agencies are aware that manufacturers already do program the engine controller to recognize a low battery situation and provide alerts or other signals as warranted. This override simply allows th e main engine to idle temporarily

if a backup sy stem is not available to provide this power. Another override that the agencies are adopting is for extreme ambient temperatures, which was also requested by commenters including ATA, DTNA, EMA/TMA, Cummins and TRALA . In the case where the cabin temperature cannot be maintained within a reasonable range due to extreme hot or cold ambient conditions, this provision will allow main engine idle for cabin heating or cooling purposes. If there is no auxiliary he ating or cooling s ys tem installed, or if it is inadequate or fails , the agencies recognize that allowing override of the AES may assist in providing for driver safet y , and possibly avoid adverse health impacts from unreasonable cabin conditions in unexpect ed situations . The agencies have not found regulations defining or governing acceptable tractor cabin or sleeper berth temperatures. 104 In general, temperatures below 50 degrees F can result in impaired dexterity . Temperature is not the sole indicator of unreasonable conditions, since env ironmental effects such as humidity and solar radiation, and individual conditions such as weight, cardiovascular health, and clothing also contribute to the safet y of an individual. 105 Tractors with “arctic” packages are av ailable on the market, with insulation properties that reduce demand from heating and cooling sources. Nonetheless, the agencies recognize that our rules do not specify cab design,***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 73 nor do they

mandate an auxiliary

power source. Preliminary testing indicat es that some devices may

have trouble cooling or heating the cabin to the desired temperature for a duration of 10 hours with ambient temperatures at 100 or zero degrees F, respectively . 106 Thus, this override allows the main engine to idle if an auxiliary sy stem is not able to provide needed heating or cooling. The fifth override provision adopted is for the case where the engine coolant temperature is too low to protect the engine. ATA commented that this is one of the flexibilities the agencies should consider. Manufacturers specify acceptable temperature ranges for engine coolant s, which if not heated sufficiently , may be too viscous to properl y circulate. With engine block heaters and insulate d lines, coolant temperature is normally maintained within acceptable levels , often above 60 degrees C (140 degrees F) . The agencies are adopting this AES override for low coolant temperature, in the case that the main engine must be allowed to idle accord ing the manufacturer's engine protection guidanc e . The agencies expect this provision will be effectuated rarel y, and the duration of main engine idle will be short for each instance, with coolant temperatures rising quickl y to acceptable levels. 107 The sixth override provision adopted is for the case where the main engine must idle to operate a power take - off. ATA commented that this is one of the flexibilities the agencies should consider. The agencies understand that certain sleeper cab Class 8 t ractors emplo y a power take - off to perform work such as pumping liquid cargo or tipping a container, or for cargo refrigeration. This override is offered because the fuel and emissions reductions targeted in this program are primarily those from extended i dle during mandated driver rest periods, rather than periods performing useful work. 

### 2.5.5 **Vehicle Speed Limiters** As discussed above, the power required to move a vehicle increases as the vehicle speed increases. Travelling at lower speeds provides additional efficiency to the vehicle performance. Most vehicles today have the ability

to electronicall y control the maximum vehicle speed through the engine controller. This feature is used today by fleets and owners to provide increased safety and fuel econom y. Currentl y, these features are designed to be able to be changed b y the owner and/or dealer. The impact of this feature is dependent on the difference between the governed speed and the speed that would have been travelled, which is dependent on road type , state speed limits, traffic congestion, and other factors. The agencies will be assessing the benefit of a vehicle speed limiter b y reducing the maximum drive cycle speed on the 65 mph Cruise mode of the cycle. The maximum speed of the drive cycle is 65 mph, therefore any vehicle speed limit with a setting greater than this will show no benefit for purposes of these regulations, but may still show benefit in the real world in states where the interstate truck speed limit is greater than the national average of 65.5 mph. The benefits of this simple technology are widel y recognized. The American Trucking Association (ATA) developed six recommendations to reduce carbon emissions**Regulatory Impact Anal ysis** 

2 - 74

from trucks in the United States. Their first recommendation is to enact a national truck speed limit of 65 mph and require that trucks manufactured after 1992 have speed governors set at not greater than 65 mph. 108 The SmartWay program includes speed management as one of their key Clean Freight Strategies and provides informati on to the public regarding the benefit of lower highway

speeds. 109 Some countries have enacted regulations to reduce truck speeds. For example, the United Kingdom introduced regulations in 2005 which require new trucks used for goods movement to have a vehicle speed limiter not to exceed 90 km/hr (56 mph). 110 The Canadian Provinces of Ontario and Quebec developed regulations which took effect in January 2009 that requires on - highway commercial heavy - dut y trucks to have speed limiters which limit the truc k’s speed to 105 km/hr (65 mph) . 111 Many truck fleets consider speed limiter application a good business practice in their operations. A Canadian assessment of heav y - duty truck speed limiters estimated that 60 percent of heav y truck fleets in North America use speed limiters. 112 Con Way Freight, Con Way Truckload, and Wal - Mart currentl y govern the speeds of their fleets between 62 and 65 mph. 113A potential disbenefit of this technology is the additional time required for goods movement, or loss of productivity . The elasticity between speed reduction and productivity loss has not been well defined in industry . The Canadian assessment of speed limiters cited above found that the fuel savings due to the lower operating speeds outweigh any productivity losses. A general consensus among the OEMs is that a one percent decrease in speed might lower productivit y b y approximately 0.2 percent. 114 In this final rule, the agencies are allowing the use of vehicle speed limiters as a way of complying with the Class 7 and 8 combination tractor vehicle standards

– that is, a VSL value is an optional input in GEM. For purposes of these regulations, the agencies are assuming that there is no additional capital cost associated with a vehicle speed limiter. There are also no hardware requirements for this feature, only software control strategies. Nearl y all heav y - dut y engines today are electronically controlled and are capable of being programmed for a maximum vehicle speed. The onl y new requirement for truck manufacturers th at the agencies are imposing through this rulemaking is to offer a vehicle speed limiter which is protected from tampering and cannot be changed by the fleet or truck owner. This technology is required to be used for the full useful life of the vehicle to obtain the GHG emissions reduction. The vehicle speed limiter is technically applicable to all truck classes which operate at high speeds. However, due to the structure of the first phase of the Heav y - Duty truck program, it is only

applicable to the Clas s 7 - 8 tractors. The benefits of the vehicle speed limiter are assessed through the use of alternate High Speed Cruise cycles. The baseline cycle contains a constant 65 mph cruise. As discussed in much more detail in Section II. B.3.g of the final rule, the agencies are providing some adjustments to the VSL requirement s for the final rulemaking to accommodate flexibilities desired b y the trucking industry. The agencies will continue to***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 75 allow VSLcredit for m anufacturers who provide “soft top” and expiration feature s to be programmed into PCMs in order to provide additional flexibility for fleet owners and so that fleets who purchase used vehicles have the ability to have different VSL policies than the original owner of the vehicle. The agencies are finalizing an approach which allows manufacturers to provide a vehicle speed limiter with a limited life to address concerns about resale value of trucks with a VSL . The age ncies will discount the value of the vehicle speed limiter based on the number of miles in which it is preset relative to the lifetime of the tractor. The agencies calculated the lifetime miles of a combination tractor based on EPA’s MOVES model as 1, 2 59 , 000 miles. The lifetime value is weighted to take into account the survival rate of heavy duty trucks, as shown above in Table 2 - 28 . Inusing a soft top feature, a manufacturer will be required to provide to the agencies a functional description of the “soft top” control strategy including calibration values, the speed setting for both the hard limit and the soft top and the maximum tim e per day

the control strategy

could allow the vehicle to operate at the “soft top” speed limit at the time of certification and identify the use of the “soft top” VSLon the vehicle label. This information will be used to derive a factor to discount the VSLinput used in GEM modeling to determine the fuel consumption and GHG emissions performance of the vehicle. The equation to derive the GEM input for VSL for sy stems with an expiration is the following, as shown in Equation 2 - 2 . **Eq uation**  **2 -**  **2 : Discounted**  **VSL Equation**  VSL input for GEM = Expiration Factor * [Soft Top Factor* Soft Top VSL + (1 - Soft Top Factor) * VSL] + (1 - Expiration Factor)*65 mph The expiration factor is equal to the number of miles at expiration divided by 1, 259 , 000 miles The soft top factor is equal to the maximum number of hours that a vehicle may travel at the soft top VSLin a 10 hour day divided by

7.3 hours for sleeper cabs or 3.9 hours for day cabs based on the agencies’ drive cycle weighting factors . The number of hours spent travelling at each cycle is included in Table 2 - 29 . **Table 2**  **- 29**  **: Soft Top Factor Calculations**

Sleeper Cab Day Cab VMT weighting of 65 mph cycle 0.86 0.64 VMT weighting of 55 mph cycle 0.09 0.17 VMT weighting of Transient cycle 0.05 0.19 Average speed of 65 mph cycle 65 65 Average Speed of 55 mph cycle 55 55 Average Speed of Transient cycle 15.3 15.3 Miles per day

travelled at 65 mph 474.2 252.4 Miles per day

travelled at 55 mph 49.6 67.0 Miles per day

travelled at transient 27.6 74.9**Regulatory Impact Anal ysis** 

2 - 76

Total miles per day 551 394 Hours per day spent at 65 mph 7.3 3.9 Hours per day

spent at 55 mph 0.9 1.2 Hours per day

spent at transient 1.8 4.9 Total hours per day 10.0 10.0 

### 2.5.6 **Automated Manual Transmission** Most heavy - dut y trucks use manual transmissions with 8 to 18 gear ratios available. The most common transmissions for line haul applications have 10 ratios with an overdrive top gear. Torque - converter automatic transmissions, similar to those used in passenger cars, are used in some stop/go truck applications but are mor e expensive and do not have an efficiency

advantage in line - haul applications. Automated manual transmissions have been available on the market for over 10 ye ars now and are increasing in market share. Automated manuals have a computer to decide when to sh ift and use pneumatic or h ydraulic mechanisms to actuate the clutch and hidden shift levers. An automated manual can shift as quickly as the best driver, and the shift schedule can be tailored to match the characteristics of the engine and vehicle. This re duces variability of fuel consumption and CO 2 emissions between drivers, with all drivers achieving results closer to those of the best drivers. In application, there would be a fuel econom y improvement proportional to the number of non - fuel - conscious dri vers in a fleet. 115 

### 2.5.7 **Class 7 and**  **8 Tractor Baseline Assessment** The agencies developed the baseline tractor for each subcategory to represent an average 2010 model ye ar tractor. The approach taken by the agencies was to define the individual inputs to GEM. For example, the agencies evaluated the industry ’s tractor offerings and conclude that the average tractor contains a generall y aerodyn amic shape (such as roof fairings) and avoid classic features such as exhaust stacks at the b - pillar which increase drag. The agencies consider a baseline truck as having “conventional” aerodynamics. The baseline rolling resistance coefficient f or today ’s fleet is 7.8 kg/metric ton for the steer tire and 8.2 kg/metric ton for the drive tire, based on sales weighting of the top three manufacturers based on market share. 116 However, today there is a large spread in aerodynamics in the new tractor fl eet. Trucks are sold that may reflect classic styling, or are sold with conventional or SmartWay aerodynamic packages. **Table 2**  **- 30**  **Class 7 and 8**  **Baseline Attributes** CLASS 7 CLASS 8 Day Cab Day Cab Sleeper Cab Low Roof Mid

Roof High

Roof Low Roof Mid Roof High Roof Low Roof Mid Roof High Roof **Aerodynamics (Cd)** Baseline 0.77 0.87 0.73 0.7 7 0. 87 0.73 0.77 0.87 0.70 **Steer Tires (Crr kg/metric ton)** ***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 77 Baseline 7.8 7.8 7.8 7.8 7.8 7.8 7.8 7.8 7.8 **Drive Tires (Crr kg/metric ton)** Baseline 8.2 8.2 8.2 8.2 8.2 8.2 8.2 8.2 8.2 **Weight Reduction ( lb**  **)** Baseline 0 0 0 0 0 0 0 0 0 **Extended Idle Reduction (gram CO 2**  **/ton -**  **mile reduction)** Baseline N/A N/A N/A N/A N/A N/A 0 0 0 **Vehicle Speed Limiter** Baseline -- -- -- -- -- -- -- -- -- **Engine** Baseline 2010 MY

11L Engine 2010

MY 11L Engine 2010

MY 11L Engine 2010 MY

15L Engine 2010 MY

15L Engine 2010 MY

15L Engine 2010 MY

15L Engine 2010 MY

15L Engine 2010 MY

15L Engine 

### 2.5.8 **Class 7 and**  **8 Tractor Standards Derivation** As discussed in more detail in Section II. B and III.A of the preamble, EPA and NHTSA project that CO 2 emissions and fuel consumption reductions can be achieved through the increased penetration of aerodyn amic technologies, low rolling resistance tires, weight reduction, extended idle reduction technologies, and vehicle speed limiters. The agencies believ e that h ybrid powertrains in line - haul applications will not be cost - effective in the time frame of the rule. T he NAS report stated that the effectiveness of h yb rid powertrains installed in tractors is 10 percent , but 6 percent of it was attributed to idle reduction which is already addressed in the HD program, at a cost of $25,000. 117 T he agencies also are not includ ing drivetrain technologies in the standard setting process, as discussed in Section II .B.3 .h.iv of the preamble , and instead are choosing to allow the continuation of the current truck specifying process that is working well today . The agencies investigated the possibility of essentially forcing SmartWay

technologies (aerodyn amics, tires, and extended idle) into 100 percent of Class 7 and Class 8 tractors. However, as discussed below, the agencies realize that there are some restrictions which prevent 100 percent penetrati on. Therefore, the agencies took the approach of evaluating each technology

and finalizing what we deem as the maximum feasible penetration into each tractor regulatory

category . The next sections describe the effectiveness of the individual technologies , the costs of the technologies, the penetration rates of the technologies into the regulatory

categories, and finally

the derivation of the final standards. 2.5.8.1 **Technology Effectiveness** The agencies’ assessment of the technology effectiveness was developed through the use of the GEM . Table 2 - 31 describes the model inputs for the range of Class 7 and 8 tractor technologies.**Regulatory Impact Anal ysis** 

2 - 78 **Table 2**  **- 31**  **: GEM Inputs** Class 7 Class 8 Day Cab Day Cab Sleeper Cab Low / Mid Roof High Roof Low / Mid Roof High Roof Low Roof Mid Roof High Roof **Aerodynamics (Cd)** Frontal Area (m 2 ) 6.0 9.8 6.0 9.8 6.0 7.7 9.8 Bin I 0.77 / 0.87 0.7 9 0.77 /

0.87 0.7 9 0.77 0.87 0.7 5 Bin II 0.71 / 0.82 0.7 2 0.71 /

0.82 0.7 2 0.71 0.82 0.6 8 Bin III 0.6 3 0.6 3 0. 60 Bin IV 0.5 6 0.5 6 0.5 2 Bin V 0.5 1 0.5 1 0.4 7 **Steer Tires (Crr kg/metric ton)** Baseline 7.8 7.8 7.8 7.8 7.8 7.8 7.8 Level I 6.6 6.6 6.6 6.6 6.6 6.6 6.6 Level II 5.7 5.7 5.7 5.7 5.7 5.7 5.7 **Drive Tires (Crr kg/metric ton)** Baseline 8.2 8.2 8.2 8.2 8.2 8.2 8.2 Level I 7.0 7.0 7.0 7.0 7.0 7.0 7.0 Level II 6.0 6.0 6.0 6.0 6.0 6.0 6.0 **Weight Reduction (lbs.)** Control 400 400 400 400 400 400 400 **Extended Idle Reduction (gram CO 2**  **/ton -**  **mile reduction)** Control N/A N/A N/A N/A 5 5 5 **Vehicle Speed Limiter** Control N/A N/A N/A N/A N/A N/A N/A

2.5.8.2 **Class 7 and**  **8 Tractor Application Rates** Vehicle manufacturers often introduce major product changes together, as a package. In this manner the manufacturers can optimize their available resources, including engineering, development, manufacturing and marketing activities to create a product with multiple new features. In addition, manufacturers recognize that an engine and truck will need to remain competitive over its intended life and meet future regulatory requirements. In some limited cases, manufacturers may implement an individual techno logy outside of a vehicle’s redesign cycle. For consistency with these industry practices, the agencies have created a set of vehicle technology packages for each regulatory subcategory . With respect to the level of technology required to meet the standards, NHTSA and EPA established technology application caps. The first ty pe of cap was established based on the application of common fuel consumption and CO 2 emission reduction technologies into***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 79 the different ty

pes of tractors. For example, idl e reduction technologies are limited to Class 8 sleeper cabs based on the assumption that day cabs are not used for overnight hoteling. Idle reduction technologies such as APUs and cabin heaters can reduce workday idling associated with day cabs. Ho wever, characterizing idling activity for this segment in order to quantify the benefits of idle reduction technology is complicated by

the variet y of duty cycles found in the sector. Idling in tractors used for pick - up and delivery construction, refuse, and other ty pes of vocational vehicles varies significantl y. Given the great variety of duty cycles and operating conditions of vocational vehicles and the timing of these rules, it is not feasible at this time to establish an accurate baseline for quanti fying the expected improvements which could result from use of idle reduction technologies. A second t ype of constraint was applied to most other technologies and limited their penetration based on factors such as market demands. The impact of aerodynamic s on a truck’s efficiency increases with vehicle speed. Therefore, the usage pattern of the truck will determine the benefit of various aerodynamic technologies. Sleeper cabs are often used in line haul applications and drive the majority of their miles on the highway travelling at speeds greater than 55 mph. The industry has focused aerodynamic technology

development, including SmartWay certified tractors, on these types of trucks. Therefore the agencies are finalizing the most aggressive aerodynamic t echnology penetration in this regulatory subcategory . All of the major manufacturers today offer at least one truck model that is SmartWay designated . The 2010 NAS Report found that manufac turers indicated that aerodyn amic improvements which yield 3 to 4 percent fuel consumption reduction or 6 to 8 percent reduction in Cd values, beyond technologies used in today ’s SmartWay

trucks are achievable. 118 The final standards are predicted on an aerodynamic penetration rate for Class 8 sleeper cab high roof cabs of 20 percent of Bin IV , 70 percent Bin III , and 10 percent Bin II . The small percent age of Bin II tractor aerodynamics is for applications that do not qualify as vocational tractors but may still not be able to use f eatures such as chassis skirts which are prone to damage in off - road applications . Tire rolling resistance is only one of several performance criteria that affect t ire selection. The characteristics of a tire also influence durability, traction control, vehicle handling and comfort. A single performance parameter can easil y be enhanced, but an optimal balance of all the criteria must be maintained. Tire design req uires balancing performance, since changes in design may change different performance characteristics in opposing direction. Similar to the discussion regarding lesser aerodynamic technology penetration in tractor segments other than sleeper cab high roof , the agencies believe that low rolling resistance tires should not be applied to 100 percent of all tractor segments. The agencies are instead basing the standards on application rates that vary by subcategory

to reflect the on/off

- ro ad application of some tractors which require a different balancing of traction versus rolling resistance , but do not qualify for the off

- road vocational tractor exemption . Weight reductions can be achieved through single wide tires replacing dual tires an d lighter weight wheel material or through the use of other light weight components as specified in Table 2 - 23 . Single wide tires can reduce weight by over 160 pounds per axle. Aluminum**Regulatory Impact Anal ysis** 

2 - 80

wheels used in lieu of steel wheels will reduce weight b y over 80 po unds for a dual wheel axle. L ight weight aluminum steer wheels and aluminum single wide drive wheels and tires package will provide a 670 pound weight reduction over the baseline steel steer and dual drive wheels. In comments to the agencies, Volvo and A TA stated that not all fleets can use single wide tires and as a result they stated the weight reduction requirement should be reduced. In response, the agencies are finalizing as direct GEM inputs additional light weight components that can be used to ac hieve the 400 pound weight reduction for tractors. Additional weight reduction opportunities exist with the use of aluminum or light weight steel in steps, clutch housings, and other components listed in Table 2 - 23 . Idle reduction technologies provide significant reductions in fuel consumption and CO 2 emissions. There are several different technologies available to reduce idling , like a uxiliary power units, diesel fired heaters, and battery powered units. Each of these technologies has a different level of fuel consumption and CO 2 emissions. Therefore, the emissions reduction value varies b y technology . Also, our discussions with manufacturers indicate that idle technologies are sometimes installed in the factory , but it is also a common practice to have the units installed after the sale of the truck. Therefore, we would like to continue to incentivize this practice while providing some certainty that the overnight idle operations will be eliminated. Therefore, we are allowing the installation of only an automatic engine shutof

f, without override capability , to qualify for idle emission reductions. We are finalizing a 100 percent penetration rate for this technology (and several override options not proposed, to account for driver safety and comfort concerns raised in the comme nts) and have estimated that 30 percent of the current fleet already employ s this technology

meaning that 70 percent are estimated to add this technology . Consistent with proposal, v ehicle speed limiters may be used as a technology to meet the standard, but this technology was not used as part of the technology package on which the standard is based . The comments received from stakeholders did not address the agencies’ concerns discussed in the proposal, specifically the risk of re quiring VSLin situations that are not appropriate from an efficiency perspective because it may lead to additional truck trips to deliver the same amount of freight. H The agencies continue to believe that we are not in a position to determine how many ad ditional trucks would benefit from the use of a VSL with a setting of less than 65 mph (a VSL with a speed set at or above 65 mph will show no CO 2 emissions or fuel consumption benefit on the drive cycles included in this program). We will monitor the ind

ustry ’s use of VSL in this program and may consider using this technology in standard setting in the future. Table 2 - 32 provides the final application rates for each technology by regulatory subcategory .

H See 75 FR at page 74223***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 81 **Table 2**  **- 32**  **: Application Rates** Class 7 Class 8 Day Cab Day Cab Sleeper Cab Low/Mid Roof High Roof Low/Mid Roof High Roof Low Roof Mid Roof High Roof **Aerodynamics (Cd)** Bin I 4 0% 0% 4 0% 0% 3 0% 3 0% 0% Bin II 6 0% 30% 6 0% 30% 7 0% 7 0% 10% Bin III 60% 60% 70% Bin IV 10% 10% 20% Bin V 0% 0% 0% **Steer Tires (Crr kg/metric ton)** Baseline 40% 30% 40% 30% 30% 30% 10% Bin I 50% 60% 50% 60% 60% 60% 70% Bin II 10% 10% 10% 10% 10% 10% 20% **Drive Tires (Crr kg/metric ton)** Baseline 40% 30% 40% 30% 30% 30% 10% Bin I 50% 60% 50% 60% 60% 60% 70% Bin II 10% 10% 10% 10% 10% 10% 20% **Weight Reduction (lbs.)** Control 100% 100% 100% 100% 100% 100% 100% **Extended Idle Reduction (gram CO 2**  **/ton -**  **mile reduction)** Control Not Applicable Not

Applicable Not

Applicable Not

Applicable 100% 100% 100% **Vehicle Speed Limiter** Control -- -- -- -- -- -- --

The agencies used the technology inputs and technology

application rates in GEM to develop the fuel consumption and CO 2 emissions standards for each subcategory of Class 7/8 combination tractors. The agencies derived a scenario truck for each subcategory by weighting the individual GEM input parameters included in Table 2 - 31 by the application rates in Table 2 - 32 . For example, the Cd value for a Class 8 Sleeper Cab High Roof scenario case was derived as ( 10 percent x 0. 66 ) + ( 70 percent x 0. 58 ) + ( 20 percent x 0. 50 ) , which is equal to a Cd of 0. 57 . Similar calculations were done for tire rolling resistance, weight reduction, idle reduction, and vehicle speed limiters. To account for the two engine standards, EPA and NHTSA are finalizing the use of a 2014 model year fuel consumption map in GEM t o derive the 2014 model year tractor standard and a 2017 model year fuel consumption map to derive the 2017 model year tractor standard. 119 The agencies then ran GEM with a single set of vehicle inputs, as shown in Table 2 - 33 , to derive the final standards for each subcategory . The final standards and percent reductions are included in Table 2 - 34 . **Table 2**  **- 33**  **Inputs to the GEM m odel for Class 7**  **and 8**  **Tractor Standard Setting**  CLASS 7 CLASS 8**Regulatory Impact Anal ysis** 

2 - 82 Day Cab Day Cab Sleeper Cab Low Roof Mid Roof High Roof Low Roof Mid Roof High Roof Low Roof Mid Roof High Roof **Aerodynamics (Cd)** 0.73 0.84 0.65 0.7 3 0. 84 0.65 0.73 0.84 0.59 **Steer Tires (Crr kg/metric ton)** 6.99 6.99 6.87 6.99 6.99 6.87 6.87 6.87 6.54 **Drive Tires (Crr kg/metric ton)**  7.38 7.38 7.26 7.38 7.38 7.26 7.26 7.26 6.92 **Weight Reduction ( lb**  **)** 400 400 400 400 400 400 400 400 400 **Extended Idle Reduction (gram CO 2**  **/ton -**  **mile reduction)** N/A N/A N/A N/A N/A N/A 5 5 5 **Vehicle Speed Limiter**

-- -- -- -- -- -- -- **Engine** 2014/17 MY 11L Engine 2014/17

MY 11L Engine 2014/17

MY 11L Engine 2014/17

MY 15L Engine 2014/17

MY 15L Engine 2014/17

MY 15L Engine 2014/17

MY 15L Engine 2014/17

MY 15L Engine 2014/17

MY 15L Engine***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 83 **Table 2**  **- 34**  **Tractor Standards and Percent Reductions** Class 7 Class 8 Day Cab Day Cab Sleeper Cab Low Roof Mid Roof High Roof Low Roof Mid Roof High

Roof Low

Roof Mid

Roof High

Roof 2014 Model Year (voluntary for NHTSA program) 2014 MY Voluntary Fuel Consumption Standard (gallon/1000 ton - mi le) 10. 5 11.7 12.2 8.0 8. 7 9.0 6. 7 7. 4 7. 3

2014 MY CO 2 Standard (grams CO 2 /ton - mi le) 107 119 124 81 8 8 92 68 76 7 5 Percent Reduction 8% 7% 10 % 8 % 7 % 11% 15% 14 % 21% 2017 Model Year and later 2017 MY Fuel Consumption Standard (gallon/1000 ton - mi le) 10. 2 11.3 11. 8 7. 8 8. 4 8. 7 6. 5 7. 2 7.1

2017 MY CO 2 Standard (grams CO 2 /ton - mi le) 104 115 120 80 86 89 66 73 72 Percent Reduction 10% 10% 13 % 10 % 10% 13 % 17% 17 % 23%



### 2.5.9 **Class 7 -**  **8 Tractor Technology Costs** The technology

costs associated with the tractor defined in Table 2 - 33 for each of the tractor subcategories are listed in Table 2 - 35 .**Regulatory Impact Anal ysis** 

2 - 84

**Table 2**  **- 35**  **Estim ated Class 7**  **- 8 Tractor Technology Costs, Inclusive of Markups and Penetration Rates,**  **Applicable in the 2014MY ( 2009**  **dollars)** Class 7 Class 8 Day Cab Day Cab Sleeper Cab Lo w & Mid Roof High Roof Lo w & Mid Roof High Roof Lo w Roof Mid Roof High Roof **Aerodynam ics**  Bin III & Bin IV $ 675 $ 924 $ 675 $ 924 $ 962 $ 983 $ 1, 627 **Steer Tires** Lo w Rolling Resistance $ 68 $ 68 $ 68 $ 68 $ 68 $ 68 $6 8 **Drive Tires** Lo w Rolling Resistance $ 63 $ 63 $ 126 $ 126 $ 126 $ 126 $12 6 **Weight Reduction** Weight Package $1, 200 $1, 536 $ 1,980 $ 1,980 $ 3,275 $ 3,275 $ 1,980 **Extended Idle Reduction** Auxiliary Power Unit N/A N/A N/A N/A $3, 819 $3, 819 $3, 819 **Vehicle Speed Limiter** Control N/A N/A N/A N/A N/A N/A N/A



### 2.6 **Class 2b -**  **8 Vocational Vehicles 2.6.1**  **Tires** As discussed in more detail in Section III.D of the preamble, the range of rolling resistance of tires used on vocational vehicles (Class 2b

– 8) today is large. The competitive pressure to improve rolling resistance of these tires has been less than that found in the Class 8 line haul tire market. Due to the drive cycles ty pical for these applications, tire traction and durability are weighed more heavil y in a purchaser’s decision than rolling resistance. Therefore, the agencies believe that a regulatory program that incentivizes the optimization of tire rolling re sistance, traction and durability can bring about GHG emission and fuel consumption reductions from this segment. It is estimated that low rolling resistance tires used on Class 3

– 6 trucks would improve fuel economy by 2.5 percent 84 relative to tires not designed for fuel efficiency . Tires used on vocational vehicles (Class 2b

– 8) t ypically carry less load than a Class 8 line haul vehicle. T hey

are also designed for resistance to scrubbing and curb damage . Because they

carry less load and high scrubbing, tires used on vocational vehicles are can retreaded as man y as five times.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 85 Since the NPRM , the agencies have conducted additional research on tire rolling resistance for m edium - and heav y - d ut y applications. EPA has conducted tire rolling resistance testing to help inform the final rulemaking. 122 The testing measured the RR C of tires representing 16 different vehicle applications for C lass 4

– 8 vocational vehicles . The testing included approximately 5 samples each of both steer and drive tires for each application. The tests were conducted by two independent tire test labs, Standards Testin g Lab (STL) and Smithers - Rapra (Smithers). Overall, a total of 156 medium - and heav y - dut y tires were included in this testing, which was comprised of 88 tires covering various commercial vocational vehicle types, such as bucket trucks, school buses, city delivery vehicles, city

transit buses and refuse haulers among others; 47 tires intended for application to tractors; and 21 tires classified as light - tr uck (L T) tires intended for Class 4 vocational vehicles such as delivery vans. The test results for 88 commercial vocational vehicle tires (19.5” and 22.5” sizes) showed a test average RR C of 7.4 kg/metric ton , with results ranging from 5.4 to 9.8. T o comply with the proposed vocational vehicle fuel consumption and GHG emissions standards using improved tire rolling resistance as the compliance strategy , a manufacturer would need to achieve an average tire RR C value of 8.1 kg/metric ton . 123 The measure d average RR C of 7.4 kg/metric ton is thus better than the average value that would be needed to meet vocational vehicle standards. Of th ose eight y - eight tires tested, twenty tires had RR C values worse than 8.1 kg/metric ton, two were at 8.1 kg/metric to n, and sixty- six tires were better than 8.1 kg/metric ton. Additional data anal ys es examining the tire data b y tire size to determine the range and distribution of RRC values within each tire size showed each tire size generall y had tires rang ing from approximately 6.0 to 8.5 kg/metric ton, with a small number of tires in the 5.3

– 5.7 kg/metric ton range and a small number of tires in a range as high as 9.3

– 9.8 kg/ton. Review of the data showed that for each tire size and vehicle ty pe, the majo rity of tires tested would enable compliance with vocational vehicle fuel consumption and GHG emission standards. Finally , the 21 LT tires intended for Class 4 vocational vehicles were comprised of two sizes; L T225/75R16 and LT245/75R16 with 11 and 10 samples tested, respectivel y. Some auto manufacturers have indicated that RR C values for tires fitted to these Class 4 vehicles ty

picall y have a higher RRC value s than tires found on commercial vocational vehicles because of the smaller diameter wheel size an d the I SO testing protocol. 124 The test data showed the average RR C for L T225/75R16 tires was 9.1 kg/metric ton and the average for LT245/75R16 tires was 8.6 kg/metric ton. The range for the LT225/75R16 tires spanned 7.4 to 11.0 125 and the range for the LT245/ 75R16 tires ranged from 6.6 to 9.8 kg/metric ton. Overall, the average for the tested LT tires was 8. 9 kg/metri c ton. Analy sis of the EPA test data for all vocational vehicles, including LT tires, shows the test average RR C is 7. 7 kg/metri c ton and with a standard deviation of 1. 2 kg/metric ton. R eview of the data thus shows that for each tire size and vehicle type, the re are man y tires available that would enable compliance with the proposed standards for vocational vehicles**Regulatory Impact Anal ysis** 

2 - 86

and tractors except for LT tires for Class 4 vocational vehicles where test results show the majority of these tires are worse than 8.1 kg/metri c ton. The agencies also reviewed the RRC data from the tires that were tested at both the STLand Smithers laboratories to assess inter - laboratory and test machine variability . The agencies conducted statistical anal ys is of the data to gain better understanding of lab - to - lab correlation and developed an adjustment factor for data measured at e ach of the test labs . When applied, this correction factor showed that for 77 of the 80 tires tested, the difference between the original RRC and a value corrected RR C was 0.01 kg/metric ton. The values for the remaining three tires were 0.03 kg/metric t on, 0.05 kg/metric ton and 0.07 kg/metric ton. Based on these results, the agencies believe the lab - to - lab variation for the STLand Smithers laboratories would have very small effect on measured RR C values. Further, in anal yz ing the data, the agencies co nsidered both measurement variability and the value of the measurements relative to proposed standards. The agencies concluded that although laboratory - to - laboratory and test machine - to - test machine measurement variability exists, the level observed is no t excessive relative to the distribution of absolute measured RRC performance values and relative to the proposed standards. Based on this, the agencies concluded that the test protocol is reasonable for this program , but are making some revisions to the vehicle standards . For vocational vehicles, the rolling resistance of each tire will be measured using the ISO 28850 test method for drive tires and steer tires planned for fitment to the vehicle being certified. Once the test RR C values are obtained, a manufacturer will input the RR C values for the drive and steer tires separately into the GEM where, for vocational vehicles, the vehicle load is distributed equally over the steer and drive tires . Once entered, the amount of GHG reduction attributed to tire rolling resistance will be incorporated into the overall vehicle compliance value. The following table provides the revised target RRC values for vocational vehicles for 2014 and 2017 model years that are used to determine the vehicle standards.

**Table 2**  **- 36**  **: Vocational Vehicle –**  **Target RR C**  **Values for GEM Input** 2014 MY 2017 MY Tire Rolling Resistance (kg/metric ton) 7.7 kg/metric ton 7.7 kg/metric ton These target values are being revised based on the significant availability of tires for vocational vehicles applications which have performance better than the originall y proposed 8.1 kg/metric ton target. As just discussed, 63 of the 88 tires tested for vocat ional applications had RR C values better than the proposed target. The tires tested covered fitment to a wide range of vocational vehicle ty pes and classes; thus agencies believe the original target value of 8.1 kg/metric ton was possibly too lenient after reviewing the testing data. Therefore, the agencies believe it is appropriate to reduce the proposed vehicle standard based on performance of an RRC target value of 7.7 kg/metric ton for non - LT tire type. As discussed previously , this value is the test average of all vocational tires tested (including LT) which takes a conservative approach over setting a target based on the average of only the non - LT Vocational tires tested. For L T tires, based on both the test data and the comments from AAPC and Ford Mo tor Company , the agencies recognize the need to provide an adjustment. In lieu of having two sets of L ight Heavy - Duty vocational vehicle standards, the agencies are***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 87 finalizing an adjustment factor which applies to the RRC test results for L T tires. The age ncies developed an adjustment factor dividing the overall vocational test average RRC of 7.7 by the LT Vocational Average of 8.9. This yields an adjustment factor of 0.87. For LT vocational vehicle tires, the measured RRC values will be multiplied by the 0 .87 adjustment factor before entering the values in the GEM for compliance. The agencies have estimated the costs of low rolling resistance tires as shown in Table 2 - 37 . These costs include a low complexity I CM of 1. 18 and flat - portion of the curve learning would be considered appropriate for these technologies. **Table 2**  **- 37**  **Estim ated Costs for Low Rolling Resistance Tires on Vocational Vehicles in the 2014MY**  **( 2009**  **$)** LIGHT - HEAVY & MEDIUM - HEAVY HEAVY - HEAVY Low rolling resistance steer tires $ 68 $ 68 Low rolling resistance drive tires $ 94 $ 126 Package cost (including penetration rates) $81 $97 

### 2.6.2 **Other Evaluated Technologies for Vocational Vehicles**  2.6.2.1 **Aerodynamics** Aerodynamic drag is an important aspect of the power requirements for Class 2b through 8 vocational vehicles. Because aerody namic drag is a function of the cube of vehicle speed, small changes in the aerodyn amics of a vocational vehicle reduces drag, fuel consumption, and GHG emissions. The great variety of applications for vocational vehicles result i n a wide range of operational speed profiles (i.e., in - use drive cycles) , with many weighted toward lower speeds where aerodynamic improvement benefits are less pronounced. In addition, vocational vehicles have a wide variety of configurations (e.g., util ity trucks with aerial devices, transit buses, and pick - up and delivery trucks) and functional needs (e.g., ground clearance, towing, and all weather capability). This specialization can make the implementation of aerodynamic features impractical and, where specialt y markets are limited, make it unlikely

that per - unit costs will lower with sales volume. This technology

is not expected as a result of the final standards. 

### 2.6.2.2 **Hybrid Powertrains** A hy brid electric vehicle (HEV) is a vehicle that combines two or mor e sources of propulsion energy , where one uses a consumable fuel (i.e. gasoline or diesel), and one is rechargeable (during operation, or by another energy

source). Hy

brid technology

is established in the U.S. market and more manufacturers are adding h yb rid models to their lineups. Hy

brids reduce fuel consumption through three major mechanisms:**Regulatory Impact Anal ysis** 

2 - 88

 Powertrain control strategy can be developed to operate the engine at or near its most efficient point most of the time.  The internal combustion engine can be opti mized through downsizing or modifying the operating cycle. Power loss from engine downsizing can be mitigated b y emplo yi ng power assist from the secondary power source.  Some of the energy

normally lost as heat while braking can be captured and stored in th e energy

storage s ys tem for later use.  The engine is turned off when it is not needed, such as when the vehicle is coasting or stopped, such as extending idle conditions. Hy brid vehicles utilize some combination of the above mechanisms to reduce fuel consumption and CO 2 emissions. A final mechanism to reduce fuel consumption, available only to plug - in hy

brids, is by

substituting the petroleum fuel energy with energy

from another source, such as the electric grid. Plug - in hy brids may be most su itable for some applications which travel short distances such as local pickup and delivery . The effectiveness of fuel consumption and CO 2 reduction depends on the utilization of the above mechanisms and how aggressivel y the y are pursued. One area where this variation is particularl y prevalent is in the choice of engine size and its effect on balancing fuel efficiency and performanc e. Some manufacturers choose not to downsize the engine when applying hy

brid technologies depending on the power from the hy brid s ys tem components. In these cases, performance is improved, while fuel efficiency improves significantly

less than if the eng ine was downsized to maintain the same performance as the conventional version. While this approach of not downsizing the engine has been used in passenger cars occasionall y, it is more likely to be used for trucks where towing, hauling and/or cargo capac ity is an integral part of their performance requirements. In these cases, if the engine is downsized, the battery

can be quickly

drained during a long hill climb with a heavy load, leaving onl y a downsized engine to carry the entire load. Because cargo capability is critical truck attribute, manufacturers are hesitant to offer a truck with downsized engine which can lead to a significantl y diminished towing performance with a low battery, and therefore engines are traditionally

not significantl y downsize d for these vehicles. In addition to the purel y hy brid technologies, which decreases the proportion of propulsion energy

coming from the fuel by

increasing the proportion of that energy coming from electricity , there are other steps that can be taken to improve the efficiency of auxiliary functions (e.g., power - assisted steering or air - conditioning) which also reduce CO 2 emissions and fuel consumption. Optimization of the auxiliary functions, together with the hy brid technologies, is collectively referred to as vehicle or accessory load electrification because they generally use electricity

instead of engine power. Fuel efficiency gains achieved onl y through electrification are considered in a separate section although these improvements may be combined w ith the hybrid sy stem. A hy brid drive unit is complex and consists of discrete components such as the electric traction motor, transmission, generator, inverter, controller and cooling devices. Certain types***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 89 of drive units may

work better than others for specific vehicle applications or performance requirements. Several types of motors and generators have been developed for h ybrid - electric drive sy stems, many

of which merit further evaluation and development on specific applications. Series HEVs ty picall y have larger motors with higher power ratings because the motor alone propels the vehicle, which may be applicable to Class 3 - 5 applications. In parallel hy brids, the power plant and the motor combine to propel the vehicle. Motor and engine torque are usual ly

blended through couplings, planetary gear sets and clutch/brake units. The same mechanical components that make parallel heav y - dut y h ybrid drive units possible can be designed into series hybrid drive units to decrease the size of the electric motor(s) and power electronics. An electrical energy

storage s ys tem is needed to capture energy from the generator, to store energy

captured during vehicle braking events, and to return energy when the driver demands power. This technology has seen a tremendous amount of improvement over the last decade and recent ye ars. Advanced battery technologies and other t ypes of energy storage are emerging to give the vehicle its needed performance and efficiency gains while still providing a product with long life. The foc us on the more promising energy storage technologies such as nickel metal - hydride (NiMH) and lithium technology batteries along with ultra capacitors for the heav y - dut y fleet should yield interesting results after further research and applications in the l ight - dut y fleet. Heav y - dut y h ybrid vehicles also use regenerative braking for improved fuel economy , emissions, brake heat, and wear. A conventional heav y vehicle relies on friction brakes at the wheels, sometimes combined with an optional engine retarder or driveline retarder to reduce vehicle speed. During normal braking, the vehicle’s kinetic energy is wasted when it is converted to heat b y the friction brakes. The conventional brake configuration has large components, heav y brake heat sinks, and high te mperatures at the wheels during braking, audible brake squeal, and consumable components requiring maintenance and replacement. Hy brid electric sy stems recover some of the vehicle’s kinetic energy through regenerative braking, where kinetic energy is captured and directed to the energy storage sy stem. The remaining kinetic energy is dissipated through conventional wheel brakes or in a driveline or transmission retarder. Regenerative braking in a hy brid electric vehicle can require integration with the vehic le’s foundation (friction) braking s ystem to maximize performance and safety. Today ’s sy stems function by simultaneousl y using the regenerative features and the friction braking s ys tem, allowing only some of the kinetic energy to be saved for later use. Op timizing the integration of the regenerative braking s ys tem with the foundation brakes will increase the benefits and is a focus for continued work. This type of h ybrid regenerative braking s ys tem improves fuel econom y, GHG emissions, brake heat, and wear. In addition to electric h ybrid systems, EPA is experimenting with a Class 6 hydraulic hy brid that achieves a fuel econom y increase superior to that of an electric hybrid. 126 Inthis ty pe of s ys tem, deceleration energy is taken from the drivetrain by an inl ine hydraulic pump/motor unit by

pumping hydraulic fluid into high pressure cylinders. The fluid, while not compressible, pushes against a membrane in the cylinder that compresses an inert gas to 5,000 PSIor more when full y charged. Upon acceleration, the energy stored in the pressurized tank**Regulatory Impact Anal ysis** 

2 - 90

pushes hydraulic fluid back into the drivetrain pump/motor unit, allowing it to motor into the drivetrain and assist the vehicle’s engine with the acceleration event. This heavy - dut y truck hy brid approach has been dem onstrated successfully , producing good results on a number of commercial and military

trucks. Nevertheless, c onsidering the diversity of the heavy - dut y fleet along with the various ty pes of h yb ridization, the results are diverse as well. The percentage s avings that can be expected from h ybridization is very sensitive to duty cycle. For this reason, anal ys es and efforts to promote h ybrids often focus on narrow categories of vehicles. For vocational vehicles other than tractor - trailers, h yb rid technologies are promising, because a large fraction of miles driven by

these trucks are local and under stop - and - go conditions. One study claims hy bridization could almost double fuel econom y for Class 3 - 5 trucks and raise Class 6 - 7 fuel econom y b y 71 percent in city driving, at costs that will decline rapidl y in the coming ye ars with the incremental cost of the hy brid vehicles depending on the choice of technology and the year, the later being a surrogate for progress towards economies of scale and experience with the technology 80 . Another Argonne National L ab study considering only truck Classes 2 and 3 indicates possible fuel efficiency gains of 40 percent 84 . The Hy brid Truck Users Forum has published a selection of four t ypes as good candidates for h ybridization; Class 4 - 8 Specialty Trucks, including utility

and fire trucks; Class 4 - 6 urban delivery trucks, including package and beverage delivery ; Class 7 and 8 refuse collection; and Class 7 and 8 less - than load urban delivery

trucks. The average fuel economy increase over the five cycles is 93 percent for the Class 3 - 4 truck and 71 percent for the Class 6 - 7 vehicle. Stop - and - go truck driving includes a fraction of idling conditions during which the truck base engine consumes fuel but produces no economicall y useful output (e.g., movement of goods, or repositioning of the truck to a new location). Hy brid propulsion sy stems shut off the engine under idling conditions or situations of low engine power demand. Trucks that have high fractions of stop - and - go freight transport activities within their driving cycles, such as medium - duty

package and beverage delivery trucks, may

be appropriate candidates for hy bridization. L ong - haul trucks have a lower proportion of short - term idling or low engine power demand in their duty cycles because of traffic conditions or frequency stops compared to medium - duty

trucks in local ser

vices. Based on the results of hy bridization effects modeling, medium - dut y trucks in local service (e.g., delivery) can reduce energy use b y 41.5 percent 127

. Another 2009 report states that a 10 percent fuel consumption decrease could be achieved if idle red

uction benefits were realized and a 5 percent improvement considering for on - road onl y 128

. In heav y - dut y h yb rid research, the industry role will be represented by the heavy hy brid team members (e.g. Allison Transmission, Arvin - Meritor, BAE S ys tems, and Eat on Corporation). The Department of Energy is pursuing heavy

hy brid research through the Freedom CAR and Vehicle Technologies Program. The Department of Transportation (Federal Transit Administration) is playing a role in demonstration of these vehicles for the transit bus market. The Department of Defense is working with heav y h ybrid equipment suppliers to develop and demonstrate h ybrid vehicles for military applications, and has already made significant investments in hy brid technology

to reduce fuel consumption and improve their ability

to travel silently

in combat situations. The Environmental Protection Agency has participated in the heavy hy brid arena through its work on mechanical hy brids for***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 91 certain applications as discussed previousl y. The U.S. Department of Energy ’s 21st Century Truck Partnership (21CTP) has established challenging goals for improving fuel economy and pollutant emissions from heav y - dut y vehicles including a diverse set of vehicles ranging from approximately

8,500 lb GVW to 100,000+ lb GVW 60

. Despite the significant future potential for h ybrids discussed above, there are no simple solutions applicable for each heav y - dut y h ybrid application due to the large vocational vehicle fleet variation. A choice must be made relative to the requirements and prio rities for the application. Challenges in motor subsy stems such as gear reductions and cooling s ys tems must be considered when comparing the specific power, power density, and cost of the motor assemblies. High speed motors can significantl y reduce weight and size, but they require speed reduction gear sets that can offset some of the weight savings, reduce reliability and add cost and complexity . Air - cooled motors are simpler and generall y less expensive than liquid cooled motors, but they

will be larger and heavier, and they require access to ambient air, which can carry

dirt, water, and other contaminants. L iquid - cooled motors are generally smaller and lighter for a given power rating, but they may require more complex cooling sy stems that can be avoided with air - cooled versions. Various coolant options, including water, water - gl yc ol, and oil, are available for liquid - cooled motors but must be further researched for long term durability . Electric motors, power electronics, electrical safety, regenerative b raking, and power - plant control optimization have been identified as the most critical technologies requiring further research to enable the development of higher efficiency hy brid electric propulsion sy stems. In addition, because manufacturers will incur expenses in bringing h yb rids to market, and because bu ye rs do not purchase vehicles on the basis of net lifetime savings (see Section VIII.A.4 of the preamble) , the cost - effectiveness of hy brids may not in itself translate into market success, and measures to promote h ybrids are needed until costs come down. Vocational vehicles have diverse duty c ycl es, and they are used to a far greater extent for local trips. Some of the technologies are much less effective for trucks that generall y drive at low speeds an d therefore have limited applicability. Conversel y, these trucks are the best candidates for h ybrid technology, because local trips ty picall y involve a large amount of stop and - go driving, which permits extensive capture of braking and deceleration energy . In summary , man y technologies that appl y to cars do not apply to heavy - duty

trucks and there is a common perception that investments in passenger car (light - duty vehicle) technology

can easily

benefit heavy - dut y trucks. This group of vehicles is very dive rse and includes tractor - trailers, refuse and dump trucks, package delivery vehicles and buses. The life expectancy

and dut y cycles for heavy - duty vehicles are about ten times more demanding than those for light - duty

vehicles, technologies and solutions f or the fleet must be more durable and reliable. Although a new generation of components is being developed for commercial and military

HEVs, more research and testing are required. Due to the complexity

of the heav y - dut y fleet, the variation of h ybrid s ys tem reported fuel efficiency

gains and the growing research and testing

– vehicle h yb ridization is not**Regulatory Impact Anal ysis** 

2 - 92

mandated nor included in the model for calculation of truck fuel efficiency and GHG output. Vehicle h ybridization is feasible on both tractor and vocational applications but must be tested on an individual basis to an applicable baseline to realize the s ys tem benefits and net fuel usage and GHG reductions. **2.6.2.2.1 EPA Testing of a Hybrid Tra**  **nsit Bus** EPA conducted a h yb rid transit bus test to gather experience in testing h yb rids and evaluate the GHG emissions and fuel consumption benefits. This section provides an overview of the study

and its results. However, as noted above, the agencies do not consider hy brid powertrains to be part of the basis for the standard during this first rulemaking. Following coastdown testing, in - use emissions testing was conducted on each bus using portable emissions mea surement s ys tems meeting subpart J of 40 CFR 1065. Each bus was operated over two routes, which were meant to simulate normal transit bus operation. The first route was comprised entirely of t ypical urban stop/go driving, with a number of bus stops along the 4.75 mile route. The second route was comprised of roughl y half urban driving and half highway

operation, reaching a maximum speed of approximately 60 MPH. This route was approximately

5.75 miles in length. Fuel economy

could be calculated using two me thods: through integration of the instantaneous fuel rate broadcast b y the ECU (ECU method) or through a carbon balance of the exhaust gases (Carbon Balance Method). Both methods provided repeatable results, however the ECU method tended to consistently yi eld approximately

5 percent lower fuel consumption on both vehicles. This bias appears to be due to small differences in predicted fuel flow versus measured exhaust carbon, particularly during deceleration where the ECU predicts a complete fuel cut - off. S ince the carbon balance method yields more conservative results, all fuel consumption data presented has been calculating using this method. Figure 2 - 4 presents a comp arison of the fuel economy of both buses over the two test routes. Each vehicle was tested at least 3 times over each route, and in several cases up to 10 repeats of each route were conducted. The error bars represent the standard deviation over the repl icates of each route. Over both routes, the h yb rid showed a significant fuel econom y benefit over the conventional bus. Over route 1 (urban onl y), this benefit was greatest and approached 37 percent. Over route 2 (mixed urban/highway), fuel economy was s till improved by

over 25 percent. Much of this benefit is likely attributable to the regenerative braking and launch assist capability of the hy brid sy stem since there is no idle shut - off of the engine. A secondary

benefit to the regenerative braking s ys te m is a significant increase in brake service intervals, which was highlighted in discussions with a bus fleet operator.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 93 **Figure 2**  **- 4**  **Hybrid and Conventional Bus Fuel Economy (mpg)**

Figure 2 - 5 presents the CO 2 emissions over each route on a work - specific basis. For comparison, Figure 2 - 6 , presents CO 2 normalized by the mileage travelled. Characterizing the CO 2 reduction due to the hybrid s ys tem, both methods show significant decreases in emissions. The work - specific basis may provide a more accurate comparison in this case, since environmental effects are better accounted for (i.e. driver aggressiveness, traffic, etc). This is evident when comparing the variation over the course of testing, represented b y the standard deviation. The variability on a work - specific basis is nearl y half that of using the distance - based metric. Fuel Economy vs Route

5.52 5.15 6.95

7.04

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0

Route 1 Route 2FuelEconomy(mpg) Conventional Hybrid**Regulatory Impact Anal ysis** 

2 - 94 **Figure 2**  **- 5**  **Hybrid and Conventional Bus CO 2**  **Emission Rates (g/bhp -**  **hr)**

**Figure 2**  **- 6**  **Hybrid and Conventional Bus CO 2**  **Emission Rates (g/m ile)** 

Figure 2 - 7 (a - d) compares the CO 2 emissions rate (in g/s) during typical launch (starting from a stop) events in both buses. Both vehicles showed a spike in CO 2 emissions when starting from a stop. However, this spike was much more attenuated with the hy brid bus, which demonstrates the ability of the launch assist system to reduce CO 2 emissions. The magnitude of this attenuation varied depending on the exact event, however reductions of over 50 percent were not uncommon. Also worth noting is that near the 0.35 mile mark on Figure 2 - 7 - d (lower - right), the CO 2 emissions are near zero, suggesting that the vehicle is maintaining a speed of approximately 15 MPH solely

on electric power. CO2 Emissions vs Route 602 624

410

396

0 100 200 300 400 500 600 700

Route 1 Route 2CO2(g/bhp-hr) Conventional Hybrid

CO2 Emissions vs Route

1859 1995

1467

1442

0 500 1000 1500 2000 2500

Route 1 Route 2CO2(g/mile) Conventional Hybrid***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 95 **Figure 2**  **- 7**  **Hybrid and Conventional Bus CO 2**  **Emission Rates (g/s)**

a b

c d Other observations through this testing suggest significant complexity in the calibration of the h ybrid powertrain, presumabl y with the intent of reducing fuel consumption. One example is the set of engine speed - torque points over a give n route (see Figure 2 - 8 ). The calibration of the h ybrid powertrain (red) shows distinct patterns for where the engine operates. First, the engine is less frequently loa ded at, or near idle speed. Second, the engine frequentl y operates at 1200 RPM, which is the lowest speed at which peak torque is available. Third, when more power is required (beyond 100 percent torque at 1200 RPM), the engine tends to operate along the maximum torque curve as RPM is increased. Keeping engine speed as low as possible reduces frictional losses, thus increasing efficiency. In contrast, the speed - torque points of the conventional bus show a much more random distribution and propensity

for o perating at lower engine loads. 0 5 10 15 20 25 30 35 40 45 50

0 0.1 0.2 Distance (miles)Speed(MPH)orCO2(g/s) Conv-MPH Hybrid-MPH Conv - CO2 Hybrid-CO2

0 5 10 15 20 25 30 35 40 45 50

0.1 0.2 0.3 Distance (miles)Speed(MPH)orCO2(g/s) Conv-MPH Hybrid-MPH Conv - CO2 Hybrid-CO2

0 5 10 15 20 25 30 35 40 45 50

0 0.1 0.2 Distance (miles)Speed(MPH)orCO2(g/s) Conv-MPH Hybrid-MPH Conv - CO2 Hybrid-CO2

0

5 10 15 20 25 30 35 40 45 50

0.2 0.3 0.4 Distance (miles)Speed(MPH)orCO2(g/s) Conv-MPH Hybrid-MPH Conv - CO2 Hybrid-CO2**Regulatory Impact Anal ysis** 

2 - 96 **Figure 2**  **- 8**  **Hybrid and Conventional Bus Operating Map Com parison** 

In summary , the h ybrid powertrain has demonstrated significant opportunity in this testing for reduction of fuel consumption and CO 2 emissions in transit bus applications. Testing over ty

pical bus routes showed up to a 37 percent reduction in both fuel consumption and CO 2 emissions. A summary of these finding is presented in Table 2 - 38 . These reductions can be attributed to three features of the h ybrid powertrain. First, electric launch assist facilitated through regenerative braking. Second, calibration of the engine to o perate in the most efficient regions of the speed - torque map. Third, electric - only drive at lower speeds was witnessed occasionally . **Table 2**  **- 38**  **Hybrid Powertrain Benefit** Conventional Hy

brid Benefit Avg CoV Avg CoV mpg or g/mile percent Route 1 MPG 5.15 8.2% 7.04 5.5% 1.89 37%

CO 2 (g/mile) 1995 8.0% 1442 5.5% 553 28% CO 2 (g/bhp - hr) 624 3.7% 396 5.3% 228 37% Route 2 MPG 5.52 8.0% 6.95 5.3% 1.43 26%

CO 2 (g/mile) 1859 7.9% 1467 5.5% 392 21% CO 2 (g/bhp - hr) 602 4.0% 410 1.7% 192 32% 0 20 40 60 80 100 120

500 1000 1500 2000 2500 Engine Speed (RPM)EngineLoad(%) Conventional Hybrid***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 97 

### 2.6.2.3 **Other Vocational Vehicle Technologies** The agencies assessed other vehicle technologies , such as idle reduction, advanced drivetrains, and weight reduction, and have concluded that they may have the potential to reduce fuel consumption and GHG emissions from at least certain vocational vehicles, but the agencies have not been able to estimate baseline fuel consumption and GHG emissions levels for each t ype of vocational vehicle and for each type of technology, given the wide variety of models and uses of vocational vehicles. I dle reduction technologies such as APUs and cabin heaters can reduce workday idling associated with vocational vehicles. However, characterizing idling activity for the vocational segment in order to quantify the benefits of idle reduction technology is complicated by

the variet y of dut y c ycl es found in the sector. Idling in school buses, fire trucks, pick - up trucks, delivery trucks, and other ty

pes of vocational vehicles varies significantly . Given the great variet y of dut y c ycl es and operating conditions of vocational vehicles and the timing of these rules, it is not feasible at this time to establis h an accurate baseline for quantifying the expected improvements which could result from use of idle reduction technologies. Similarly , for advanced drivetrains and advanced transmissions determining a baseline configuration, or a set of baseline configurations, is extremely difficult given the variety of trucks in this segment. The agencies do not believe that we can legitimately base standard stringency

on the use of technologies for which we cannot identify baseline configurations , because abse nt baseline emissions and baseline fuel consumption, the emissions reductions achieved from introduction of the technology cannot be quantified. For some technologies, such as weight reduction and improved auxiliaries

– such as electrically

driven power steering pumps and the vehicle’s air conditioning sy stem -- the need to limit technologies to those under the control of the chassis manufacturer further restricted the agencies’ options for incorporating the technologies into the final rules. For example , lightweight components that are under the control of chassis manufacturers are limited to a very few components such as frame rails. Considering the fuel efficiency and GHG emissions reduction benefits that will be achieved b y finalizing these rules in the timeframe proposed, rather than delaying in order to gain enough information to include additional technologies, the agencies have decided to finalize standards that do not assume the use of these technologies and will consider incorporating them in a later action applicable to later model ye ars. 

### 2.7 **Air Conditioning** Air conditioning (A/C) systems contribute to GHG emissions in two way s – direct emissions through refrigerant leaka ge , and indirect exhaust emissions due to the extra load on the vehicle’s engine to provide power to the air conditioning sy stem. Hydrofluorocarbon (HFC) refrigerants, which are powerful GHG pollutants, can leak from the A/C sy stem. This includes the dire ct leakage of refrigerant as well as the subsequent leakage associate d with maintenance and servicing, and with disposal at the end of the vehicle’s life. No other vehicle**Regulatory Impact Anal ysis** 

2 - 98

sy stem has associated GHG leakage. 129 The current widely - used refrigerant

– R134a, has a high global warming potential (GWP) of 1430. 130 Due to the high GWP of this HFC, a small leakage of the refrigerant has a much greater global warming impact than a similar amount of emissions of CO 2 or other mobile source GHGs. Heav y - dut y ai r c onditioning s ys tems today are similar to those used in light - duty applications. However, differences may exist in terms of cooling capacit y (such as sleeper cabs have larger cabin volumes than day cabs), s ys tem layout (such as the number of evaporators), and the durability requirements due to longer truck life. However, the component technologies and costs to reduce direct HFC emissions are similar betwe en the two ty pes of vehicles. The quantity

of indirect GHG emissions from A/C use in heavy - dut y truck s relative to the CO 2 emissions from driving the vehicle and moving freight is very small. Therefore, a credit approach for improved A/C sy stem efficiency is not appropriate for this segment of vehicles because the value of the credit is too small to prov ide sufficient incentive to utilize feasible and cost - effective air conditioning leakage improvements. For the same reason, including air conditioning leakage improvements within the main standard would in many instances result in lost control opportuniti es. Therefore, EPA is finalizing that truck manufacturers be required to meet a low leakage requirement for all air conditioning sy stems installed in 2014 model year and later trucks, with one exception. EPA is not establishing leakage standards for Class 2b - 8 Vocational Vehicles at this time due to the complexity in the build process and the potential for different entities besides the chassis manufacturer to be involved in the air conditioning s ys tem production and installation , with consequent difficulties in developing a regulatory s ys tem. 

### 2.7.1 **Refrigerant Leakage** Based on measurements from 300 European light - duty vehicles (collected in 2002 and 2003), Schwarz and Harnisch estimate that the average HFC direct leakage rate from mo dern A/C sy stems was estimated to be 53 g/y r. 131 This corresponds to a leakage rate of 6.9 percent per year. This was estimated b y extracting the refrigerant from recruited vehicles and comparing the amount extracted to the amount originall y filled (as per the vehicle specifications). The fleet and size of vehicles differs from Europe and the United States, therefore it is conceivable that vehicles in the United States could have a different leakage rate. The authors measured the average charge of refrige rant at initial fill to be about 747 grams (it is somewhat higher in the U.S. at 770g), and that the smaller cars (684 gram charge) emitted less than the higher charge vehicles (883 gram charge). Moreover, due to the climate differences, the A/C usage patterns also vary between the two continents, which may influence leakage rates. Vincent et al., from the California Air Resources Board estimated the in - use refrigerant leakage rate to be 80 g/yr . 132 This is based on consumption of refrigerant in commercial fleets, survey s of vehicle owners and technicians. The study assumed an average A/C charge size of 950 grams and a recharge rate of 1 in 16 years (lifetime). The recharges occurred when the s ys tem was 52 percent empt y and the fraction recovered at end - o f - life was 8.5 percent .***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 99 Since the A/C sy stems are similar in design and operation between light - and heav y duty vehicles, and emissions due to direct refrigerant leakage are significant in all vehicle ty pes, EPA is finalizing a leakage standard which is a “percent refrigerant leakage per year” to assure that high - quality , low - leakage components are used in each air conditioning sy stem design. The agency

believes that a single “gram of refrigerant leakage per year” would not fairl y address the variety of air conditioning s ys tem designs and layouts found in the heavy duty truck sector. EPA is finalizing a standard of 1.50 percent leakage per year for Heavy Duty Pickup Trucks and Vans and Class 7/8 Tractors. The final standard was derived from the vehicles with the largest sy stem refrigerant capacity based on the Minnesota GHG Reporting database. 133 As shown in Figure 2 - 9 , the average percent leakage per year of the 2010 model year vehicles in the upper quartile in terms of refrigerant capacity was 1.60 percent (for reference, in the 2010 L ight - Dut y GHG rule, the average was estimated to be 2.7 percent, based on a leakage rate of 20.7 g/y r and a sy stem capacit y of 770 g).

**Figure 2**  **- 9**  **Distribution of Percentage Refrigerant Loss Per Year -**  **Vehicles in Upper Quartile of A/C**

**System Refrigerant Capacity (from** **2010 Minnesota Reporting Data).** By requiring that all heavy - dut y tru cks achieve the leakage level of 1.50 percent per ye ar, roughl y half of the vehicles in the 2010 data sample would need to reduce their leakage rates, and an emissions reduction roughly comparable to that necessary to generate direct emission credits unde r the light - dut y vehicle program would result. See 75 FR at 25426 - 247. 0. 0000 0. 0200 0. 0400 0. 0600 0. 0800 0. 1000 0. 1200 0. 1400 0. 1600

0. 00 0. 10 0. 20 0. 30 0. 40 0. 50 0. 60 0. 70 0. 80 0. 90 1. 00 1. 10 1. 20 1. 30 1. 40 1. 50 1. 60 1. 70 1. 80 1. 90 2. 00 2. 10 2. 20 2. 30 2. 40 2. 50 2. 60 2. 70 2. 80 2. 90 3. 00**F r** **e q** **u e** **n c** **y**

**Annual Pe rc**  **enta ge**  **R efri**  **ge ra**  **nt Loss**  **(% /yr)**  - Annua l Percentage Lo ss = Yearl y Leak Rate / Re fr ig eran t Cap acity

- 53 vehicles in da ta se t (2010 model year only)

- Sys tem ref rigeran t cap acity ranges f ro m 810 g (C hevrolet Expres s) to1 531 g (For d E - Series w/dua l evaporators )

- Yearly % leak

rate ran ges fr om 0. 78%/yr (C hevrolet E xpres s) to 2. 77%/ yr ( To yot a Lan d C ruis er w/dual evaporator and co olbox) Medi an = 1. 44 %/yr Average = 1. 60 %

/yr**Regulatory Impact Anal ysis** 

2 - 100

We believe that a ye arl y sy stem leakage approach will assure that high - quality , low - leakage, components are used in each A/C sy stem design, and we expect that manufacturers will reduc e A/C leakage emissions by utilizing improved, leak - tight components. Some of the improved components available to manufacturers are low - permeation flexible hoses, multiple o - ring or seal washer connections, and multiple - lip compressor shaft seals. The availability of low leakage components in the market is being driven by the air conditioning credit program in the light - duty

GHG rule (which applies to 2012 model year and later vehicles). EPA believes that reducing A/C sy stem leakage is both highl y cost - effective and technologicall y feasible. The cooperative industry and government Improved Mobile Air Conditioning (IMAC) program has demonstrated that new - vehicle leakage emissions can be reduced b y 50 percent by

reducing the number and improving the quali ty of the components, fittings, seals, and hoses of the A/C s ys tem. 134 All of these technologies are already in commercial use and exist on some of today ’s sy stems. EPA requires that manufacturers demonstrate improvements in their A/C sy stem designs an d components through a design - based method. The method for calculating A/C Leakage is based closely

on an industry - consensus leakage scoring method, described below. This leakage scoring method is correlated to experimentally- measured leakage rates from a number of vehicles using the different available A/C components. Under th is approach, manufacturers would choose from a menu of A/C equipment and components used in their vehicles in order to establish leakage scores, which would characterize their A/C sy stem leakage performance and calculate the percent leakage per ye ar as this score divided by the sy stem refrigerant capacity . Consistent with the L ight - Duty Vehicle Greenhouse Gas Emissions rulemaking, a manufacturer would compare the components of its A/C sy stem with a set of leakage reduction technologies and actions that is based closely on that being developed through IMAC and the Societ y of Automotive Engineers (as SAE Surface Vehicle Standard J2727, August 2008 version). 135 See generall y 75 FR at 254 26. The SAE J2727 approach was developed from laboratory testing of a variety of A/C related components, and EPA believes that the J2727 leakage scoring s ys tem generall y represents a reasonable correlation with average real - world leakage in new vehicles. Li ke the IMAC approach, our proposed approach would associate each component with a specific leakage rate in grams per year identical to the values in J2727 and then sum together the component leakage values to develop the total A/C sy stem leakage. Howev er, in the heav y - dut y truck program, the total A/C leakage score is then divided the value b y the total refrigerant s ys tem capacit y to develop a percent leakage per year value. 

### 2.7.2 **System Efficiency** A program could also be developed that includes efficiency improvements. CO 2 - equivalent emissions and fuel consumption are also associated with air conditioner efficiency , since air conditioners create load on the engine. See 74 FR at 49529. However, the ag encies are not setting air conditioning efficiency standards for heav y - duty trucks, as the fuel consumption and CO 2 emissions due to air conditioning sy stems in heavy - duty trucks are***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 101 minimal (compared to their overall fuel consumption and emissions of CO 2 ). For example, EPA conducted modeling of a Class 8 sleeper cab using GEM to evaluate the impact of air conditioning and found that it leads to approximately 1 gram of CO 2 /ton - mile. Therefore, a projected 24 percent improvement of the ai r conditioning sy stem (the level projected in the light - duty GHG rulemaking), would only reduce CO 2 emissions by less than 0.3 g CO 2 /ton mile, or approximately

0.3 percent of the baseline Class 8 sleeper cab CO 2 emissions.**Regulatory Impact Anal ysis** 

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### 2.8 **Other Fuel Consumption and GHG Reducing Strategies**  There are several other types of strategies available to reduce fuel consumption and GHG emissions from trucks. For the reader’s reference, EPA and NHTSA identify several of these technologies and strateg ies below, but we note that they are outside the regulatory framework currentl y identified and will neither be required b y final standards nor were they considered in determining the stringency of the final standards . 

### 2.8.1 **Auxiliaries** The accessories on a truck engine, including the alternator, coolant and oil pumps are traditionally

mechanically

gear - or belt - driven b y the base engine. In general, the effect of accessory power con sumption in trucks is much less than in cars , but the m echanical a uxiliaries operate whenever base engines are running, which can waste energy when the auxiliaries are not needed. The replacement of mechanical auxiliaries by electricall y - driven sy stems can decouple mechanical loads from the base engine and reduce energy use. Since the average engine loads from mechanical auxiliaries are higher than those from a small generator that supplies electricity to electric auxiliaries, base engine fuel can be reduced. A reduction in CO 2 emissions and fuel consumption can be real ized by driving them electrically and only when needed (“on - demand”). The heav y and medium trucks have several auxiliary sy stems:

 Air compressor,  Hydraulic pumps,  Coolant pump,  Engine oil and fuel pumps,  Fans, and  Air conditioning compressor. The sy stems listed above, although not inclusive, can be optimized by various methods reducing fuel consumption and GHG emissions :  Electric power steering (EPS)

– is an electricall y - assisted steering s ys tem that has advantages over traditional hydraulic power steerin g because it replaces a continuously

operated h ydraulic pump, thereb y reducing parasitic losses from the accessory drive.

 Electric water pumps and electric fans - can provide better control of engine cooling. For example, coolant flow from an electric water pump can be reduced and the radiator fan can be shut off during engine warm - up or cold ambient temperature conditions which will reduce warm - up time, reduce warm - up fuel enrichment, and reduce parasitic losses. Indirect benefit may be obtained by

reduc ing the flow from the water pump electricall y during the engine warm - up period, allowing the engine to heat more rapidl y and thereb y reducing the fuel enrichment needed during cold starting of the engine.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 103  High efficiency alternators - provide greater electrical power and efficiency at road speed or at idle than conventional original equipment replacement alternators that ty picall y operate at 55 percent efficiency .  If electric power is not available - there are still some technologies that can be applied to reduce the parasitic power consumption of accessories. Increased component efficiency is one approach, and clutches can be used to disengage the alternator and air compressor when they

are not required. Many

MD/HD engines incorporate clutch ed cooling fans which can be shut off during engine warm - up , thereby not requiring electric cooling fans. Air compressors that are rotating but not creating pressure absorb about half the power of a pumping compressor, and compressors normally onl y pump a small percentage of the time in long - haul trucks. Several studies have documented the GHG reductions from electrification and/or optimization of truck auxiliaries. One study , based on a full - scaled test of a prototy pe truck that used a small generator to produce electricity, full electrification of auxiliaries reduces fuel use by 2 percent including extended idle and estimated potential reductions in modal GHG emissions are 1.4 percent . Another study recently completed by

Ricardo discussed the advantages o f electrification of engine accessories along with the potential to increase fuel econom y citing examples such as variable flow water pumps and oil pumps 136 . Potential gains may be realized in the range of 1 to 3 percent but are highl y dependent on truck typ e, size and duty cycle. In a NESC C AF study, the accessory power demand of a baseline truck was modeled as a steady state power draw of 5 kW, and 3 kW for more electrical accessories in individual vehicle configurations that included electric turbo compoun ding. The 2 kW savings versus average engine power of 100 to 200kW over a drive cycle nets roughly 1 to 2 percent savings compared to a baseline vehicle. Accurate data providing power consumption values for each discrete accessory over a range of operating conditions was not available due to the variation of the truck fleet. Based on research and industry

feedback, a simplified assumption for modeling was made that the average power demand for mechanically driven accessories is 5 kW, and the average power d emand for electrically

driven accessories is 3 kW. This provides a 2 kW advantage for the electrically

driven accessories over the entire drive cycle represent ed and is estimated to provide a 1.5 percent improvement in efficiency and reduction in CO 2 emiss ions. As a comparison, the average load on a car engine over a drive cycle may be in the 10 to 20 kW range. At this level, a 2 kW reduction in accessory loads of a passenger vehicle makes a significant difference (approximately 10 percent). Given the high er loads experienced by truck engines, accessory

demand is a much smaller share of overall fuel consumption. Accessory

power demand determined b y discrete components will be not be included in the model at this time and a power draw of 5 kW for standard ac cessories and 3 kW for electrical accessories will be used. There is opportunit y for additional research to improve upon this simple modeling approach by using actual measured data to improve the modeling assumptions.**Regulatory Impact Anal ysis** 

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### 2.8.2 **Driver training** D river training that targets fuel efficiency can help drivers recognize and change driving habits that waste fuel and increase harmful emissions. E ven highl y experienced truck drivers can boost their skills and enhance driving performance through driver training programs. 137 D riving habits that commonly waste fuel are high speed driving, driving at unnecessarily

high rpm, excessive idling, improper shifting, too - rapid acceleration, unnecessarily

frequent stops and starts, and poor route planning. Well - trained drivers can redu ce fuel consumption by appl yi ng simple techniques to address vehicle and engine speed, shifting patterns, acceleration and braking habits, idling, and use of accessories. 138 Some techniques include starting out in a gear that does not require using the thro ttle when releasing the clutch, progressive shifting (upshifting at the lowest possible rpm), anticipating traffic flow to reduce starts and stops, use of block shifting where possible (e.g., shifting from 2 nd to 5 th gear), using cruise control as appropri ate, and coasting down or using the engine brake to slow the vehicle, instead of gearing down or using the brake pedal. As discussed elsewhere in this chapter, idling can be eliminated b y the use of auxiliary power units or other idle reduction solutions that provide power or heating and cooling to the cab at a much lower rate of energy consumption. Better route planning that reduces unnecessary mileage and the frequency of empty backhauls, and takes into account factors like daily congestion patterns is an other facet of a comprehensive driver training program. Such planning can be assisted through the use of logistics companies, which specialize in such efficiencies. In its report, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy -D uty Vehicles , the National Research Council cited studies that found, on average, a five percent improvement in vehicle fuel efficiency due to driver training. 139 EPA’s SmartWay

Transport Partnership has documented the success of dozens of trucking c ompanies’ use of driver training programs. One company reported saving an average of 42 gallons per student, or 335,000 gallons of fuel per year; and, saving 837,000 gallons of fuel in the four ye ars it has had its training program in place . 140 Trucking fl eets can provide additional motivation to reward drivers for improved performance with incentive programs, which may

be monetary

or provide other fo rms of benefits and recognition . Successful programs are those that perform ongoing reviews of driver technique s , and provide assistance to improve and/or retrain drivers . While EPA and NHTSA recognize the potential opportunity to reduce fuel consumption and greenhouse gas emissions by encouraging fuel - efficient driver habits, mandating driver training for all of the nation’s truck drivers is beyond the scope of this regulat ion. However, in developing this regulation , the agencies did consider technologies that can provide some of the benefits typicall y addressed through driver training. Examples include automatic engine shutdown to reduce idling, automated or automated man ual transmissions to optimize shifting, and speed limiters to reduce high speed operation. EPA will also continue to promote fuel - efficient driving through its SmartWay program. In***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 105 addition to providing fact sheets on fuel efficient driving, 141 SmartWay is collaborating with Natural Resources Canada’s FleetSmart program to develop a web - enabled “fuel efficient driver” training course for commercial truck drivers. Once the course is developed, it will complement the agencies ’ regulatory program by

making fu el efficient driver training strategies available to any commercial truck driver. 2.8.2.1 **Replacement Tires** Original equipment (OE) tires are designed and marketed for specific applications and vehicles. Their characteristics are optimized for the specific applic ation and vehicle. Because they are not sold as OE, replacement tires are generally designed for a variety

of applications and vehicle t ypes that have different handling characteristics. The tires marketed to the replacement tire market tend to place gre ater emphasis on tread wear, and therefore often have higher rolling resistance than OE tires. The market for replacement tires is individual vehicle owners and fleet owners and not the vehicle manufacturers. Many fleets report that the cost of fuel as opposed to driver pay is its number one cost. This has resulted in a greater demand for low rolling resistance replacement tires. Both heav y - dut y and medium - duty truck fleets are looking for way s to reduce operational costs. In 2007, EPA’s SmartWay Transport Partnership introduced a means to distinguish tires based on their rolling resistance. Since 2007 the number of low rolling resistance tires available to vehicle owners and vehicle fleets has increased greatly , which is an indicator of an increase in demand. EPA expects this trend to continue. In addition, effective January 1, 2010, California Air Resource Board requires that all tractor - trailers hauling dry van trailers on any California road be equipped with SmartWay verified low rolling resistance tires; other states may

adopt this requirement. EPA expects this requirement will drive the demand for low rolling resistance tires even further. 2.8.2.2 **Retreaded Tires** The tread life of a tire is a measure of durability and some tires are designed specifi call y for greater durability. Commercial truck tires are designed to be retreaded, a process in which a new tread is bonded to the tire casing. The original tread of a tire will last any where from 100,000 miles to over 300,000 miles, depending on vehicle operation, original tread depth, tire axle position, and proper tire maintenance. Retreading can extend the tire’s useful life b y 100,000 miles or more. 142 In2005, the Tire Industry Association estimated that approximately

17.6 million retreaded truck ti res were sold in North America 143

. To maintain the quality

of the casing and increase the likelihood of retreading, a tire should be retreaded before the tread depth is reduced to its legal limit. At any time, a steer tire must have a tread depth of at leas t 4/32 of an inch and a drive tire must have a tread depth of at least 2/32 of an inch (49 CFR § 393.75). To protect the casing, a steer tire is generall y retreaded once the tread is worn down to 6/32 of an inch and a drive tire is retreaded once the**Regulatory Impact Anal ysis** 

2 - 106

trea d is worn down to 8/32 of an inch. 144 Tires used on Class 8 vehicles are retreaded as many as three times. Both the casing and the tread contribute to a tire’s rolling resistance. It is estimated that 35 to 50 percent of a tire’s rolling resistance is th e result of the tread. 61 Differences in drive tire rolling resistance of up to 50 percent for the same casing with various tread compounds have been demonstrated. For example, a fuel efficient tread (as defined b y the manufacturer) was added to two different casings resulting i n an average increase in rolling resistance of 48 percent. When a nonfuel efficient tread (also defined b y the manufacturer) was added to the same casings, the rolling resistance increased b y 125 percent on average. This characterizes the effect of the tread on the rolling resistance of a tire. Because tires can be retreaded multiple times, changes in the casing due to wear, damage and material aging may impact rolling resistance to a greater degree than would occur in an original tire. Additional ly , as evidenced above, if a tread compound different than the original tread is used, a retreaded tire can have higher or lower rolling resistance than the original tire. Since the agencies have no way of knowing whether the rolling resistance of retread ed tires will be higher or lower than the rolling resistance of the original tires, we similarly have no way

of knowing whether low rolling resistance tire benefits will continue to accrue for a vehicle’s entire lifetime. There is a cost savings associat ed with retread tires. A new retread costs between $150 and $200, compared to a new tire which costs ty picall y around $400. Since retreads are not ty picall y used on the steer axle position, this represents a savings of $1,600 to $2,000 per tractor. 

### 2.8.3 **A utomatic Tire inflation and**  **T ire**  **Pressure Monitoring System** Underinflation of tires has the potential to reduce fuel econom y b y as much as two to three percent 145 . Although most truck fleets understand the importance of keeping tires properl y inflated, it i s likely that a substantial proportion of trucks on the road have one or more underinflated tires. An industry survey conducted in 2002 at two truck stops found that fewer than half of the tires checked were within five pounds per square inch (psi) of the ir recommended inflation pressure. Twenty - two percent of the vehicles checked had at least one tire underinflated b y at least twenty psi , and four percent of the vehicles were running with at least one flat tire, defined as a tire underinflated b y fifty psi or more. The survey also found mismatches in tire pressure exceeding five percent for dual tires on axle ends. 146 A commercial vehicle tire condition study conducted by

the Federal Motor Vehicle Safety Administration (FMCSA) in 20 03 found similar indicators of poor tire inflation pressure maintenance in commercial fleets. The FMCSA concluded that only fort y - four percent of all tires on commercial vehicles were inflated within 5 psi of the recommended pressure, while over seven perc ent of all tires in operation on commercial vehicles were underinflated b y at least twenty psi. It was also determined that the rates of tires used in dual assemblies that differed in pressure b y more than 5 psi was approximately twenty percent for***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 107 tractor duals and twent y - five percent for trailer duals. Finally , the FMCSA concluded that there were significant differences in tire inflation maintenance practices between private and for - hire fleets, smaller and larger fleets, and local bus and motor coach fle ets. 147 Proper tire inflation pressure can be maintained with a rigorous tire inspection and maintenance program or with the use of tire pressure and inflation s ys tems. These s ys tems monitor tire pressure; some also automaticall y keep tires inflated to a specific level. However, while the agencies recognize that such devices could have a beneficial effect on fuel econom y, their use is not included in the regulatory framework. Notwithstanding the cited studies , the current level of underinflation of tires i n the American truck fleet is not known, 148 which means that neither a baseline value nor an estimate of the fuel savings from the use of automatic tire inflation sy stems can be quantified with certainty and thus is not included as part of the technology pac kage on which standard stringency is predicate d . Through its SmartWay

program, however, EPA does provide information on proper tire inflation pressure and on tire inflation and tire inflation pressure monitoring s ys tems. 149 

### 2.8.4 **Engine Features** Previous sectio ns 2.3.2.2 through 2.3.2.8 describe th e technologies that can be tested in an engine test cell for certification purpose and could be potentially implemented in production before the time frame of 2017. Some other technologies that cannot be easily tested in an engine test cell, but can improve engi ne fuel economy , are still worth mentioning for the reader’s reference . Examples include these technologies, such as driver rewards, load based speed control, gear down protection , and fan c ontrol offered b y Cummins’s PowerSpec . The driver reward developed by Cummins monitors and averages the driver ’s trip fuel econom y and trip idle percent time at regular intervals, seeking to modify driver behavior by offering incentives to use less fuel. Desirable driving habits, such as low percentage of idle time, and high MPG, are rewarded with higher limits on the road speed governor, cruise control or both. The load based speed control or other similar programs are designed to improve fuel economy , lower vehicle noise, and improve driver satisfaction by managing engine speed (rpm) based on real time operating conditions. During high power requirements , this ty pe of technology

enhances engine performance by providing the driver with an extended operating range. In addition to the fuel economy benefits from operating the engine at lower speeds, vehicle noise is lowered. Gear down protection offered b y Cummins is to promote increased fuel efficiency by encouraging the vehicle driver to operate as much as effectivel y possible in top gear where fuel consumption is lower. This can be done b y limiting vehicle speed in lower gears. Maximizing time in top gear means the engine runs in a lower rpm range, where fuel efficiency is best with improved durabilit y and without compromising performance. Difference between top gear and one gear down can be as much as 16 percent in fuel econom y. M ore deta iled descriptions of many technologies including those mentioned here can be viewed at Cummins’s website of http://www.powerspec.cummins.com/site/home/index.html .**Regulatory Impact Anal ysis** 

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Although these technologies mentioned in this section are not able to be tested in an engine test cell environment, thus being unable to be directl y used for benefits of certification purpose, the agenc ies encourage manufacturers to continue improving the current and d eveloping new technologies, thereb y reducing fuel consumption and greenhouse gases in a broader way . 

### 2.8.5 **Logistics** Lo gistics encompasses a number of interrelated, mostly operational factors that affect how efficiently

the overall freight transport s ys tem work s. These factors include choice of mode, carrier and equipment; packaging type and amount; delivery time; points of origin and destination; route choice, including locations of ports and distribution hubs; and transportation tracking s ys tems. T hese factor s are controlled b y the organizations that ship and receive goods. Due to the specialized nature of logistics management, organizations increasingl y rel y upon internal or outsourced business units to handle this function; many transportation providers off

er logistics management services to their freight customers. Because optimizing logistics is specific to each individual freight move, neither EPA nor NHTSA believed it is feasible to manage logistics through this regulation. However, implementing certain sy stem - wide logistics enhancements on a national level could provide benefits. As described in the 2010 NAS Report , 150 a broader national approach could include enhanced telematics and intelligent transportation s ys tems; changes to existing infrastructure to optimize modal choice; and increased truck capacity through changes to current truck weight and size limits. While such a broad transformation of our freight s ys tem is worthwhile to consider, implementing such sy stem - wide changes falls outside the scope of this regulation. As the National Research Council noted, 151 due to its complex nature, logistics management is not readily

or effectively

addressed through any

single approach or regulation; a number of complem entary

measures and alternatives are needed. Such measures can include initiatives that enable companies to better understand, measure and track the benefits of logistics optimization from an environme ntal and economic standpoint. The SmartWay program provide s uniform tools and methodologies that companies can use to assess and optimize transportation supply

chains , and that can complement any future regulatory

and nonregulatory

approaches. 

### 2.8.6 **Longer C**  **ombination V**  **ehicles, W**  **eight I**  **ncrease** Longer combinatio n vehicles (LCVs) are tractor - trailer combination s that tow more than one trailer, where at least one of the trailers e xceeds the “pup” size ( ty pically 24 - 28 feet). Because LCVs are capable of hauling more freight than a ty pical tractor - trailer combinatio n , using LCVs reduces the number of truck trips needed to carry the same amount of freight. On a fleetwide basis, this saves fuel, reduces greenhouse gas emissions, and reduces per - fleet shipping costs . A t ypical non - LC V may tow a single trailer up to 53 feet in length, or tow two pup trailers, or even be a straight truck with a pup trailer connected via a draw bar. In contrast, the t ypical LCV may consist of a tractor towing two trailers of 45 - 48 feet, and occasionall y 53 feet in length (a “turnpike dou ble”), or one of that size and one pup (a “Rocky Mountain double”), or may tow three pups (a “triple”).***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 109 Truck s consisting of a two - axle tractor combined with two one - axle trailers up to 28.5 feet are permitted on all highway s in the U.S. National Network , which consists of the interstate highway

s ys tem and certain other roads . In dividual states may permit longer L CVs to operate on roads that are not part of the National Network. They are allowed in 16 western states, but only

on turnpikes in the five states east of the Mississippi that allow them; no new states were granted permitting authority for LCVs after 1991 . 152 Regulations vary among states; some allow L CV s with more than three trailers, but only by permit. Longer length turnpike d oubles are t ypi cally restricted to tolled turnpikes. Such restrictions are based on considerations of the difficulty of operation and on expected weather conditions. Other regu lations on the ty

pes of L CVs allowed are seen in other countries; in Australia , where weather tends to be stable and dry and cross - country

roads tend to be extremely long and flat , “road trains” of up to four trailers, usuall y with three axles per traile r, are permitted. Some proponents of liberalized size and weight regulations project substantial benefits, estimating that highway freight productivity

could be doubled and costs reduced. Despite the potential benefits of L CVs, as the National Research Council noted in its recent report, there are considerations that may make LC Vs less cost - effective and less s afe , compared to traditional tractor - trailer configurations . For example, i f infrastructure (e.g., bridges with sufficient capacity ; roadway s wi th adequate lane width and curb radii for turning to accommodate an L CV safel y) are not available without traveling far from a more efficient route, or if there is insufficient opportunity for the L CV to make the most of the available volume in multiple tr ailers, then LC Vs would not be cost - effective. The increased vehicular weight of L CVs is both a safet y issue and a road maintenance issue (see discussion below on increasing vehicle weight and legal load l imits). The additional weight of extra trailers increases braking and stopping distance, and adds difficulty in maintaining speed in grade situations. With additional regard to safety, LCVs might have trouble with offtracking (when the truck’s front and rear wheels do not follow the same path, which can result in departing the lane boundaries

— a particular problem with longer L CVs ), and could increase the challenge of merging with and maneuvering in traffic. Lateral stability is a greater problem in L CVs, and leads to a greater chance of rollover, parti cularl y when the individual trailers are shorter. Also, when a vehicle is passing a LC V on a two - lane road, the period of time spent in the opposing lane (up to 2 - 3 seconds) poses another safet y problem. 153 Such safety considerations impact decisions regarding restrictions on the use of LCVs, even when they may otherwise be a cost - effective freight choice. Related, m oves to increase commercial vehicle weight limits concern not only relaxing limitations on the use of LCVs, but also increasing gross vehicle weight limits for single unit trucks and conventional tractor - trailer combinations, as well as increasing axle loa d limits and trailer lengths. Some anal ys ts cite scenarios in which such relaxations result in increased highway

freight productivity , while yi elding significant reductions in shipping costs, congestion, and total vehicle miles traveled. 154 In creasing the weight limits allows commercial freight vehicles to carry heavier loads, reducing the number of trucks required to**Regulatory Impact Anal ysis** 

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transport freight, which could potentially result in overall emissions and fuel consumption reductions. Federal law limits gross vehicle weight fo r commercial vehicles operating in the Interstate Highway

Sy stem to a maximum of 80,000 lbs. (maximum 20,000 lbs. per single axle, 34,000 lbs. per tandem axle), with permits available for certain oversize or overweight loads and exceptions allowi ng 400 lbs. more for tractors with idle reduction devices. Additional vehicle weight limitations have been set by state and local regulation s. These limitations arise from considerations of infrastructure characteristics, traffic densities, economic activ ities, freight movement, mode options, and approach to transportation design . In some cases, state limits are higher (less stringent) than federal limits . 155 While these parameters are changeable, federal weight limits on vehicles have not changed since 198 2, and limits set by

states have been frozen since 1991. In response to input from the freight transportation sector and other interested parties, the Department of Transportation, the Transportation Research Board, the General Accounting Office, and oth ers have conducted studies examining the impacts of proposals related to liberalized weight limits. R egardless of the potential benefits of such action, the anal ys es predict premature degradation of infrastructure (e.g., bridges, pavement, grades) as a consequence. Increased costs required to maintain and upgrade the highway s ys tem would impose high burdens on already - strained public resources, raising serious questions about the desirability

of relaxing weight limits, and about whether such expenditures provide adequate public good to justify

them. Safety

issues similar to those cited for LCVs enter into this debate, as do concerns with the effect on the efficiency of automotive travel, impacts on and net productivity

of other shippin g modes (particularly rail), and potential environmental and social costs. The 2010 NAS Report 156 recognized the complexities and potential trade - offs involved in increasing vehicle size and weight limits. While it is useful to discuss the potential emission and energy benefits of heavier and longer trucks, the far - reaching policy ramifications extend well beyond the scope of this rulemaking . 

### 2.8.7 **Traffic C**  **ongestion M**  **itigation** There are a wide range of strategies to reduce traffic congestion. Many of them are aimed at eliminating light - duty vehicle trips such as mass transit improvements, commute trip reduction programs, ridesharing programs, implementation of high occupancy vehicle lanes, parking pricing, and parking management programs. While focused on reducing light - dut y vehicle trips, these types of strategies would allow heav y - and medium - duty vehicles to travel on less congested roads and thereb y use less fuel and emit less CO 2 . A second gro up of strategies would directl y impact CO 2 emissions and fuel consumption from all ty

pes of vehicles. One example of these strategies is road pricing , including increasing the price of driving on certain roads or in certain areas during the most congested periods of the day . A second example is reducing the speed limits on roads and implementing measures to ensure that drivers obey the lower speed limits such as increased enforcement or adding design features that discourage excessive speeds.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 111 Some strat egies would be designed to effect trips made b y heav y - and medium - duty trucks. These would include programs to shift deliveries in congested areas to off - peak hours. Another example is to modify land use so that common destinations are closer together, which reduces the amount of travel required for goods distribution. These t ypes of congestion relief strategies have been implemented in a number of areas around the country . They are ty picall y implemented either b y state or local governments or in some cases strategies to reduce commuting trips and scheduling off - peak deliveries have been implemented b y private companies or groups of companies. 

### 2.9 **Summary of Technology Costs Used in this Analysis** Table 2 - 39 shows the technology costs used throughout this anal ys is for heavy - duty engines, vocational vehicles and combination tractors for the ye ars 2014 - 2020. Table 2 - 40 shows the technology

costs used throughout this analy sis for Class 2b and 3 diesel and gasoline trucks for the ye ars 2014 - 2020. Th ese table s reflect the impact of learning effects on estimated technology

costs. Refer to Table 2 - 2 for details on the I CMs applied to each technology

and Table 2 - 4 for the t ype of learning applied to each technology. The costs shown in the table s do not include the penetration rates so do not alway s reflect the technology ’s contribution t o the resultant package costs . One final note of clarification is that the term s “MHDDcomb” and “HHDD comb ” in the “Class” column refer speci fic all y to engines placed in combination tractors (Class 7 and 8 day cabs and sleeper cabs) .**Regulatory Impact Anal ysis** 

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**Table 2**  **- 39**  **Technology Effectiveness and**  **Costs , Inclusive of Markups,**  **by Year for Heavy**  **- duty Diesel**  **I and Gasoline Engines, Vocational**  **Vehicles , and**  **Combination Tractors**  **( 2009**  **$)** Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 A ftertreatment improvements Engine L HDD 1 - 4% $117 $114 $111 $108 $105 $103 $101 Turbo e ff iciency improvements Engine L HDD 1 - 2% $18 $18 $17 $17 $16 $16 $16 Piston improvements Engine L HDD 0.5 - 2% $3 $3 $3 $3 $2 $2 $2 Optimized water pump Engine L HDD $91 $89 $86 $84 $82 $81 $79 Optimized oil pump Engine L HDD $5 $4 $4 $4 $4 $4 $4 Optimized fuel pump Engine L HDD $5 $4 $4 $4 $4 $4 $4 Valve train friction reductions Engine L HDD $109 $106 $104 $101 $98 $97 $95 Optimized fuel rail Engine L HDD 2 - 7% $12 $12 $11 $11 $11 $10 $10 Optimized fuel injector Engine L HDD $15 $14 $14 $13 $13 $13 $13 EGR cooler improvements Engine L HDD $4 $4 $3 $3 $3 $3 $3 Cyl inder head improvements Engine LHDD $11 $11 $10 $10 $10 $10 $10 2014 MY LHDD Engine Package Engine LHDD 5% $388 $378 $368 2017 MY LHDD Engine Engine LHDD 9% $358 $349 $343 $337

I The costs included in the table represent technology costs. The engineering costs of $6.8 million per diesel engine manufacturer per year for a five year period are not included in the table.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 113 Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 Package Aftertreatment Improvements Engine MHDD 1 - 4% In R&D In R&D In R&D In R&D In R&D In R&D In R&D Turbo e ff iciency improvements Engine MHDD 1 - 2% $18 $18 $17 $17 $16 $16 $16 Piston improvements Engine MHDD 0.5 - 2% $3 $3 $3 $3 $2 $2 $2 Optimized water pump Engine MHDD $91 $89 $86 $84 $82 $81 $79 Optimized oil pump Engine MHDD $5 $4 $4 $4 $4 $4 $4 Optimized fuel pump Engine MHDD $5 $4 $4 $4 $4 $4 $4 Valve train friction reductions Engine MHDD $82 $80 $78 $76 $74 $73 $71 Optimized fuel rail Engine MHDD 2 - 7% $10 $10 $10 $9 $9 $9 $9 Optimized fuel injector Engine MHDD $11 $11 $10 $10 $10 $10 $10 EGR cooler improvements Engine MHDD $4 $4 $3 $3 $3 $3 $3 Cyl inder head improvements Engine MHDD $6 $6 $6 $6 $6 $6 $6 2014 MY MHDD Engine Package Engine MHDD 5% $234 $228 $222 2017 MY MHDD Engine Package Engine MHDD 9% $216 $211 $207 $204 Aftertreatment Improvements Engine MHDDcomb 1 - 4% In R&D In R&D In R&D In R&D In R&D In R&D In R&D Turbo e ff iciency improvements Engine MHDDcomb 1 - 2% $18 $18 $17 $17 $16 $16 $16 Piston improvements Engine MHDDcomb 0.5 - 2% $3 $3 $3 $3 $2 $2 $2 Optimized water pump Engine MHDDcomb $91 $89 $86 $84 $82 $81 $79 Optimized oil pump Engine MHDDcomb $5 $4 $4 $4 $4 $4 $4 Optimized fuel pump Engine MHDDcomb $5 $4 $4 $4 $4 $4 $4 Valve train friction reductions Engine MHDDcomb $82 $80 $78 $76 $74 $73 $71 Optimized fuel rail Engine MHDDcomb 2 - 7% $10 $10 $10 $9 $9 $9 $9 Optimized fuel injector Engine MHDDcomb $11 $11 $10 $10 $10 $10 $10 EGR cooler improvements Engine MHDDcomb $4 $4 $3 $3 $3 $3 $3 Cyl inder head improvements Engine MHDDcomb $6 $6 $6 $6 $6 $6 $6 Turbo mech anical - Engine MHDDcomb 2.5 - 5% -- -- -- $875 $852 $838 $824**Regulatory Impact Anal ysis** 

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Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 c omp ounding 2014 MY MHDD Engine Package Engine MHDDcomb 3% $234 $228 $222 2017 MY MHDD Engine Package Engine MHDDcomb 6% $1,091 $1,063 $1,045 $1,027 Aftertreatment Improvements Engine HHDD 1 - 4% In R&D In R&D In R&D In R&D In R&D In R&D In R&D Turbo e ff iciency improvements Engine HHDD 1 - 2% $18 $18 $17 $17 $16 $16 $16 Piston improvements Engine HHDD 0.5 - 2% $3 $3 $3 $3 $2 $2 $2 Optimized water pump Engine HHDD $91 $89 $86 $84 $82 $81 $79 Optimized oil pump Engine HHDD $5 $4 $4 $4 $4 $4 $4 Optimized fuel pump Engine HHDD $5 $4 $4 $4 $4 $4 $4 Optimized fuel rail Engine HHDD 2 - 7% $10 $10 $10 $9 $9 $9 $9 Optimized fuel injector Engine HHDD $11 $11 $10 $10 $10 $10 $10 Cyl inder head improvements Engine HHDD $6 $6 $6 $6 $6 $6 $6 EGR cooler improvements Engine HHDD $4 $4 $3 $3 $3 $3 $3 2014 MY HHDD Engine Package Engine HHDD 3% $234 $228 $222 2017 MY HHDD Engine Package Engine HHDD 5% $216 $211 $207 $204 Aftertreatment Improvements Engine HHDD comb 1 - 4% In R&D In R&D In R&D In R&D In R&D In R&D In R&D Turbo e ff iciency improvements Engine HHDD comb 1 - 2% $18 $18 $17 $17 $16 $16 $16 Piston improvements Engine HHDD comb 0.5 - 2% $3 $3 $3 $3 $2 $2 $2 Optimized water pump Engine HHDD comb $91 $89 $86 $84 $82 $81 $79 Optimized oil pump Engine HHDD comb $5 $4 $4 $4 $4 $4 $4 Optimized fuel pump Engine HHDD comb $5 $4 $4 $4 $4 $4 $4 Optimized fuel rail Engine HHDD comb 2 - 7% $10 $10 $10 $9 $9 $9 $9 Optimized fuel injector Engine HHDD comb $11 $11 $10 $10 $10 $10 $10 Cyl inder head improvements Engine HHDD comb $6 $6 $6 $6 $6 $6 $6 EGR cooler improvements Engine HHDD $4 $4 $3 $3 $3 $3 $3 Turbo mech anical c omp ounding Engine HHDD comb 2.5 - 5% -- -- -- $875 $852 $838 $824***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 115 Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 2014 MY HHDD Engine Package Engine HHDD comb 3% $234 $228 $222 2017 MY HHDD Engine Package Engine HHDD comb 6% $1,091 $1,063 $1,045 $1,027 Engine friction reduction Engine HDG 1 - 3% -- -- $95 $95 $95 $95 $95 Coupled valve timing Engine HDG 1 - 4% -- -- $46 $45 $44 $43 $43 Stoich GDI - V8 Engine HDG 1 - 2% -- -- $452 $442 $433 $426 $420 HD Gasoline Engine Package

– 2016 MY Engine HDG 5% -- -- $594 $582 $572 $565 $558 LRR steer tire 8.1 Truck Vocational LH 2 - 3% $68 $68 $56 $56 $47 $46 $45 LRR drive tire 8.1 Truck Vocational LH $94 $94 $78 $78 $65 $64 $62 2014MY Vehicle Package Truck Vocational LH 3% $81 $79 $77 $75 $73 $72 $71 LRR steer tire 8.1 Truck Vocational MH 2 - 3% $68 $68 $56 $56 $47 $46 $45 LRR drive tire 8.1 Truck Vocational MH $94 $94 $78 $78 $65 $64 $62 2014MY Vehicle Package Truck Vocational M H 3% $81 $79 $77 $75 $73 $72 $71 LRR steer tire 8.1 Truck Vocational HH 2% $68 $68 $56 $56 $47 $46 $45 LRR drive tire 8.1 Truck Vocational HH $126 $126 $104 $104 $87 $85 $83 2014MY Vehicle Package Truck Vocational HH 2% $97 $94 $92 $90 $87 $86 $84 Aero - Bin III Truck Class7_DayCab LowRoof 1 - 2% $1,126 $1,097 $1,068 $1,041 $1,015 $997 $981 LRR steer tire Truck Class7_DayCab LowRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class7_DayCab LowRoof $63 $61 $60 $58 $57 $56 $55 W eight reduction: Single wide tire Truck Class7_DayCab LowRoof <1% $336 $327 $319 $311 $303 $298 $293 W eight reduction: Aluminum steer wheel Truck Class7_DayCab LowRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class7_DayCab LowRoof $654 $637 $621 $605 $590 $580 $570 Air Conditioning Leakage Truck Class7_DayCab LowRoof <1% $22 $21 $21 $20 $20 $19 $19**Regulatory Impact Anal ysis** 

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Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 2014MY Vehicle Package J Truck Class7_DayCab LowRoof 3 - 4% $2,364 $2,303 $2,244 $2,186 $2,131 $2,095 $2,059 Aero - Bin III Truck Class7_DayCab HighRoof 2 - 4% $1,155 $1,126 $1,097 $1,069 $1,041 $1,024 $1,007 Aero - Bin IV Truck Class7_DayCab HighRoof 3 - 5% $2,303 $2,303 $1,907 $1,907 $1,590 $1,552 $1,515 LRR steer tire Truck Class7_DayCab HighRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class7_DayCab HighRoof $63 $61 $60 $58 $57 $56 $55 W eight reduction: Single wide tire Truck Class7_DayCab HighRoof <1% $336 $327 $319 $311 $303 $298 $293 W eight reduction: Aluminum steer wheel Truck Class7_DayCab HighRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class7_DayCab HighRoof $654 $637 $621 $605 $590 $580 $570 Air Conditioning Leakage Truck Class7_DayCab HighRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class7_DayCab HighRoof 6 - 7% $2,612 $2,551 $2,451 $2,394 $2,306 $2,266 $2,226 Aero - Bin III Truck Class8_DayCab LowRoof 1 - 2% $1,126 $1,097 $1,068 $1,041 $1,015 $997 $981 LRR steer tire Truck Class8_DayCab LowRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class8_DayCab LowRoof $126 $123 $120 $116 $114 $112 $110 W eight reduction: Single wide tire Truck Class8_DayCab LowRoof <1% $672 $654 $638 $621 $605 $595 $585 W eight reduction: Aluminum steer wheel Truck Class8_DayCab LowRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class8_DayCab LowRoof $1,308 $1,275 $1,242 $1,210 $1,179 $1,160 $1,140 Air Conditioning Leakage Truck Class8_DayCab LowRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class8_DayCab LowRoof 3 - 4% $2,871 $2,797 $2,725 $2,656 $2,588 $2,544 $2,501 Aero - Bin III Truck Class8_DayCab HighRoof 2 - 4% $1,155 $1,126 $1,097 $1,069 $1,041 $1,024 $1,007 Aero - Bin IV Truck Class8_DayCab HighRoof 3 - 5% $2,303 $2,303 $1,907 $1,907 $1,590 $1,552 $1,515 LRR steer tire Truck Class8_DayCab HighRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59

J All vehicle package costs in the table include the proposed application rates of the individual technologies used to establish the proposed standards.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 117 Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 LRR drive tire Truck Class8_DayCab HighRoof $126 $123 $120 $116 $114 $112 $110 W eight reduction: Single wide tire Truck Class8_DayCab HighRoof <1% $672 $654 $638 $621 $605 $595 $585 W eight reduction: Aluminum steer wheel Truck Class8_DayCab HighRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class8_DayCab HighRoof $1,308 $1,275 $1,242 $1,210 $1,179 $1,160 $1,140 Air Conditioning Leakage Truck Class8_DayCab HighRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class8_DayCab HighRoof 6 - 7% $3,119 $3,045 $2,933 $2,863 $2,763 $2,715 $2,668 Aero - Bin III Truck Class8_Sleeper Cab LowRoof 3 - 5% $1,374 $1,338 $1,304 $1,271 $1,238 $1,217 $1,197 LRR steer tire Truck Class8_Sleeper Cab LowRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class8_Sleeper Cab LowRoof $126 $123 $120 $116 $114 $112 $110 W eight reduction: Single wide tire Truck Class8_Sleeper Cab LowRoof <1% $672 $654 $638 $621 $605 $595 $585 W eight reduction: Aluminum steer wheel Truck Class8_Sleeper Cab LowRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class8_Sleeper Cab LowRoof $1,308 $1,275 $1,242 $1,210 $1,179 $1,160 $1,140 A ux power unit (APU ) Truck Class8_Sleeper Cab LowRoof 5 - 6% $5,455 $5,314 $5,178 $5,046 $4,917 $4,834 $4,753 Air Conditioning Leakage Truck Class8_Sleeper Cab LowRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class8_Sleeper Cab LowRoof 12 - 13% $8,271 $8,057 $7,850 $7,650 $7,455 $7,329 $7,206 Aero - Bin III Truck Class8_Sleeper Cab MidRoof 3 - 5% $1,404 $1,367 $1,332 $1,298 $1,265 $1,244 $1,223 LRR steer tire Truck Class8_Sleeper Cab MidRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class8_Sleeper Cab MidRoof $126 $123 $120 $116 $114 $112 $110 W eight reduction: Single - Truck Class8_Sleeper MidRoof <1% $672 $654 $638 $621 $605 $595 $585**Regulatory Impact Anal ysis** 

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Technology Applied to Truck type Class CO 2 eq Effectiveness 2014 2015 2016 2017 2018 2019 2020 wide tire Cab W eight reduction: Aluminum steer wheel Truck Class8_Sleeper Cab MidRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class8_Sleeper Cab MidRoof $1,308 $1,275 $1,242 $1,210 $1,179 $1,160 $1,140 A ux power unit (APU ) Truck Class8_Sleeper Cab MidRoof 5 - 6% $5,455 $5,314 $5,178 $5,046 $4,917 $4,834 $4,753 Air Conditioning Leakage Truck Class8_Sleeper Cab MidRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class8_Sleeper Cab MidRoof 11 - 12% $8,291 $8,078 $7,870 $7,669 $7,474 $7,347 $7,224 Aero - Bin III Truck Class8_Sleeper Cab HighRoof 3 - 5% $1,560 $1,520 $1,481 $1,443 $1,406 $1,382 $1,359 Aero - Bin IV Truck Class8_Sleeper Cab HighRoof 4 - 7% $2,675 $2,675 $2,215 $2,215 $1,847 $1,803 $1,760 LRR steer tire Truck Class8_Sleeper Cab HighRoof 1 - 3% $68 $66 $64 $63 $61 $60 $59 LRR drive tire Truck Class8_Sleeper Cab HighRoof $126 $123 $120 $116 $114 $112 $110 W eight reduction: Single wide tire Truck Class8_Sleeper Cab HighRoof <1% $672 $654 $638 $621 $605 $595 $585 W eight reduction: Aluminum steer wheel Truck Class8_Sleeper Cab HighRoof $546 $532 $518 $505 $492 $484 $476 Weight reduction: Aluminum single - wide wheel Truck Class8_Sleeper Cab HighRoof $1,308 $1,275 $1,242 $1,210 $1,179 $1,160 $1,140 A ux power unit (APU ) Truck Class8_Sleeper Cab HighRoof 5 - 6% $5,455 $5,314 $5,178 $5,046 $4,917 $4,834 $4,753 Air Conditioning Leakage Truck Class8_Sleeper Cab HighRoof <1% $22 $21 $21 $20 $20 $19 $19 2014MY Vehicle Package Truck Class8_Sleeper Cab HighRoof 15 - 16% $7,641 $7,458 $7,188 $7,016 $6,775 $6,658 $6,543***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 119 **Table 2**  **- 40**  **Technology Effectiveness and**  **Costs , Inclusive of Markups,**  **by Year for HD**  **Diesel and Gasoline Pickup**  **Trucks & Vans**  **( 2009**  **$)**

Technology Applied to CO2eq Effectiveness 2014 2015 2016 2017 2018 2019 Lo w friction lubricants All 0 - 1% $4 $4 $4 $4 $4 $4 Engine friction reduction HD

Gasoline 1 - 3% $ 116 $116 $116 $116 $116 $11 1 Stoich GDI V8 HD

Gasoline 1 - 2% $ 481 $ 470 $ 460 $ 460 $ 460 $ 425 8sp AT (relative to 6 sp AT) All 1.7% $ 281 $2 75 $ 2 69 $ 269 $ 2 69 $ 2 4 8 Lo w RR Tires All 1 - 2% $ 7 $ 7 $ 7 $ 7 $ 7 $6 Aero1 All 1 - 2% $5 8 $5 7 $ 5 5 $ 5 5 $ 5 5 $ 5 3 Electric/Elec tro hydraulic Power steering All 1 - 2% $1 15 $1 12 $ 10 9 $ 10 9 $ 10 9 $ 10 5 DSL engine im provements HD Diesel 4 - 6% $1 84 $1 80 $ 1 75 $ 1 71 $ 1 67 $ 1 56 DSL aftertreatment im provements HD Diesel 3 - 5% $119 $116 $ 114 $ 114 $ 114 $ 109 Im proved accessories HD Diesel 1 - 2% $ 93 $ 91 $ 8 9 $ 8 9 $ 89 $ 85 1 Mass Reduction (5%) 2b

HDGasoline 1.6% $108 $106 $103 $103 $103 $99 Mass Reduction (5%) 2b

HDDiesel 1.6% $121 $118 $115 $115 $115 $110 Mass Reduction (5%) 3

HDGasoline 1.6% $115 $112 $109 $109 $109 $105 Mass Reduction (5%) 3 HDDiesel 1.6% $127 $124 $121 $121 $121 $116 Air Conditioning Leakage All 2% $21 $21 $20 $19 $19 $18 Overall 2018 MY Package 12 - 17% $1, 048 $ 986**Regulatory Impact Anal ysis** 

2 - 120 

## References

1 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. 2 TIAX, LLC. Asse ssment of Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles. November 2009. 3 U.S. EPA. EPA Lumped Parameter Model HD Version 1.0.0.5, 2010. Docket #EPA - HQ - OAR - 2010 - 0162 . 4 NESCCAF, ICCT, Southwest Research Institute, and TIAX. Reducing Heavy - Duty Long Haul Combination Truck Fuel Consumption and CO2 Emissions. October 2009. 5 ICF International. Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions for Heavy - Duty On - Road Vehicles. July 2010. Docket Identification Number EPA - HQ - OAR - 2010 - 0162 - 0044. 6 RTI International. Automobile Industry Retail Price Equivalent and Indirect Cost Multipliers. February 2009. http://www.epa.gov/otaq/ld - hwy/420r09003.pdf ; Rogozhin, A.,et al., “Using indirect cost multipliers to estimate the total cost of adding new technology in the automobile industry,” International Journal of Production Economics (2009), doi:10.1016/j.ijpe.2009.11.031. The peer review for the RTI report is at http://www.epa.gov/otaq/ld - hwy/420r09004.pdf . 7 RTI International . Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers . July 2010. 8 Rogozhin, A.,et al., “Using indirect cost multipliers to estimate the total cost of adding new technology in the automobile industry,” International Journal of P roduction Economics (2009), doi:10.1016/j.ijpe.2009.11.031. 9 Helfand, Gloria, and Todd Sherwood, “Documentation of the Development of Indirect Cost Multipliers for Three Automotive Technologies,” August 2009. 10 RTI International . Heavy Duty Truck Retail Price Equivalent and Indirect Cost Multipliers . July 2010. 11 Rogozhin, A.,et al., “Using indirect cost multipliers to estimate the total cost of adding new technology in the automobile industry,” International Journal of Production Economics (2009), doi:1 0.1016/j.ijpe.2009.11.031. 12 See “Learning Curves in Manufacturing”, L. Argote and D. Epple, Science, Volume 247; “Tow ard Cost Buy dow n Via Learning - by - Doing for Environmental Energy Technologies, R. Williams, Princeton University, Workshop on Learning - by - Doing in Energy Technologies, June 2003; “Industry Learning Environmental and the Heterogeneity of Firm Performance, N. Balasubramanian and M. Lieberman, UCLA Anderson School of Management, December 2006, Discussion Papers, Center for Economic Studies, Was hington DC. 13 See “Learning Curves in Manufacturing”, L. Argote and D. Epple, Science, Volume 247; “Tow ard Cost Buy dow n Via Learning - by - Doing for Environmental Energy Technologies, R. Williams, Princeton University, Workshop on Learning - by - Doing in Energy Technologies, June 2003; “Industry Learning Environment s and the Heterogeneity of Firm Performance, N. Balasubramanian and M. Lieberman, UCLA Anderson School of Management, December 2006, Discussion Papers, Center for Economic Studies, Washington DC. 14 U.S. EPA and NHTSA, “Final Rulemaking to Establish Light - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards

– Joint Technical Support Document,” 2010. Last viewed on June 3, 2010 at http://www.epa.gov/otaq/climate /regulations/420r10901.pdf 15 Note that throughout the cost estimates for this HD analysis, the agencies have used slightly higher markups than those used in the 2010 - 2016 light - duty FRM. The new , slightly higher ICMs include return on capital of roughly 6 percent , a factor that was not included in the light - duty analysis.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 121 16 Note that the costs developed for low friction lubes for this analysis reflect the costs associated with any engine changes that would be required as well as any durability testing that may be required. 17 “Light - Duty Automotive Technology and Fuel Economy Trends: 1975 Through 2007”, EPA420 - S - 07 - 001, September 2007. Available at http://www.epa.gov/oms/cert/mpg/fetrends/fetrends - archive.htm (last accessed March 15, 2010 ).

18 U.S. EPA and NHTSA, “Final Rulemaking to Establish Light - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards

– Joint Technical Support Document,” 2010. Last viewed on June 3, 2010 at http://www.epa.gov/otaq/climate/regulations/4 20r10901.pdf 19 Note that throughout the cost estimates for this HD analysis, the agencies have used slightly higher markups than those used in the 2010 - 2016 light - duty FRM. The new , slightly higher ICMs include return on capital of roughly 6 percent , a fa ctor that was not included in the light - duty analysis. 20 Note that the costs developed for low friction lubes for this analysis reflect the costs associated with any engine changes that would be required as well as any durability testing that may be requir ed. 21 TIAX. Assessment of Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles, Final Report, Nov. 19, 2009, pg 4 - 15. 22 Stanton, Donald. “Enabling High Efficiency Clean Combustion.” 2009 Semi - Mega Merit Revie w of the Department of Energy. May 21, 2009. Last accessed on August 25, 2010 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_40_stanton.p df . 23 “All - new - Ford - engineered, Ford - tested, Ford - built diesel maximizes 2011 Super Duty productivity,” Ford press release, August 3, 2010. Available at: http://www.media.ford.com (last accessed June 27, 2011).

24 Stanton, Donald. “Enabling High Efficiency Clean Combustion.” 2009 Semi - Mega Merit Revie w of the Department of Energy. May 21, 2009. Last accessed on August 25, 2010 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_40_stanton.p df . 25 TIAX. Assessment of Fuel Economy Technologies for Medium - and Heavy - Duty Veh icles, Final Report, Nov. 19, 2009, pg 4 - 10. 26 “New Allison 1000 Transmission Offers Six - Speed Performance and Range Selection Mode,” GM press release, August 1, 2005. Available at: http://www.media. gm .com (last accessed June 27, 2011).

27 “T ires and Passenger Vehicle Fuel Economy,” Transportation Research Board Special Report 286, National Research Council of the National Academies, 2006, Docket EPA - HQ - OAR - 2009 - 0472 - 0146. 28 “Preliminary Vehicle Mass Estimation U sing Empirical Subsystem Influence Coefficients,” Malen, D.E., Reddy, K. Auto - Steel Partnership Report, May 2007, Docket EPA - HQ - OAR - 2009 - 0472 - 0169. Accessed on the Internet on May 30, 2009 at: http://www.a - sp.org/database/custom/Mass%20Compounding%20 - %20 Final%20Report.pdf**Regulatory Impact Anal ysis** 

2 - 122 29 “Benefit Analysis: Use of Aluminum Structures in Conjunction with Alternative Pow ertrain Technologies in Automobiles,” Bull, M. Chavali, R., Mascarin, A., Aluminum Association Research Report, May 2008, Docket EPA - HQ - OAR - 2009 - 0472 - 01 68. Accessed on the Internet on April 30, 2009 at: http://www.autoaluminum.org/dow nloads/IBIS - Powertrain - Study.pdf 30 “Future Generation Passenger Compartment - Validation (ASP 241)” Villano, P.J., Shaw , J.R., Polewarczyk, J., Morgans, S., Carpenter, J.A., Yocum, A.D., in “Lightweighting Materials

– FY 2008 Progress Report,” U.S. Department of Energy, Office of Energy Effi ciency and Renewable Energy, Vehicle Technologies Program, May 2009, Docket EPA - HQ - OAR - 2009 - 0472 - 0190. 31 “Preliminary Vehicle Mass Estimation Using Empirical Subsystem Influence Coefficients,” Malen, D.E., Reddy, K. Auto - Steel Partnership Report, May 2007, Docket EPA - HQ - OAR - 2009 - 0472 - 0169. Accessed on the Internet on May 30, 2009 at: http://www.a - sp.org/database/custom/Mass%20Compounding%20 - %20Final%20Report.pdf 32 “Lighten Up!,” Brooke, L., Evans, H. Automotive Engineering International, Vol. 117, No. 3, March 2009. 33 “2008/9 Blueprint for Sustainability,” Ford Motor Company. Available at: http:// www.ford.com/go/sustainability (last accessed February 8, 2010). 34 “Mazda to cut vehicle fuel consumption 30 percent by 2015,” Mazda press release, June 23, 2009. Available at: http://www.mazda.com/publicity/release/2008/200806/080623.html (last accessed February 8, 2010). 35 “Mazda: D on’t believe hot air being emitted by hybrid hype,” Greimel, H. Automotive News, March 30, 2009. 37 U.S. EPA and NHTSA, “Final Rulemaking to Establish Li ght - Duty Vehicle Greenhouse Gas Emission Standards and Corporate Average Fuel Economy Standards

– Joint Technical Support Document,” 2010. Last viewed on June 3, 2010 at http://www.epa.gov/otaq/climate/regulations/420r10901.pdf 38 U.S.EPA, EPA Lumped Param eter Model HD Version 1.0.0.5, 2010. Docket #EPA - HQ - OAR - 2010 - 0162 . 39 Stanton, Donald. “Enabling High Efficiency Clean Combustion.” 2009 Semi - Mega Merit Revie w of the Department of Energy. May 21, 2009. Last accessed on August 25, 2010 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_40_stanton.p df . 40 Zhang, H. Heavy Truck Engine Development & HECC. 2009 DOE Semi - Mega Merit Review, May 21, 2009. Last accessed on August 25, 2010 at http://www1. eere.energy.gov/vehiclesandfuels/pdfs/merit_review_2009/advanced_combustion/ace_42_zhang.pd f 41 Zhang, H. Detroit Diesel. “High Efficiency Clean Combustion for Heavy - Duty Engine.” August 6, 2008 presentation to DEER Conference. Last accessed on August 2 5, 2010 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2008/session5/deer08_zhang.pdf 42 NAS 2010, page 53 cites Detroit Diesel Corporation, DD15 Brochure, DDC - EMC - BRO - 0003 - 0408, April 208. 43 National Academy of Science. Technologies and Approac hes to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Pages 53 - 54. 44 Turbocompound costs derived from Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions from Heavy - Duty On - Road Vehicles. July 2010. D ocket Identification Number EPA - HQ - OAR 2010 - 0162 - 0044. Page 82 45 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 54. 46 TIAX Report. Assessment of Fuel Econo my Technologies for Medium - and Heavy - Duty Vehicles, Final Report, Nov. 19, 2009. Page 3 - 5.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 123 47 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 54. 48 Vuk, C. “Electric Turbo Compounding...A Technology Who’s Time Has Come.” 2006 DEER Conference. Last accessed on August 25, 2010 at http://www1.eere.energy.gov/vehiclesandfuels/pdfs/deer_2006/session6/2006_deer_vuk.pdf 49 TIAX, Assessment of Fuel Economy Technologi es for Medium - and Heavy - Duty Vehicles, Final Report, Nov. 19, 2009, page 4 - 15. 50 FleetOwner. com . “SCR Will Eliminate Need for Active DPF Regeneration for Volvo Trucks Next Year.” March 2009. Last accessed on June 27, 2011 at http://fleetowner.com/mid - america/volvo - trucks - scr - solution 0320/index1.html 51 TIAX. Assessment of Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles, Final Report, Nov. 19 2009. Page 4 - 16. 52 TIAX. Assessment of Fuel Economy Technologies for M edium - and Heavy - Duty Vehicles, Final Report, Nov. 19 2009. Page 4 - 20. 53 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 57. 54 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 57. 55 Assumes travel on level road at 65 MPH. (21 st Century Truck Partnership Roadmap and Technical White Papers, December 2006. U.S. Dep artment of Energy, Energy Efficiency and Renewable Energy Program. 21CTP - 003. p. 36.) 56 Reducing Heavy - Duty Long Haul Combination Truck Fuel Consumption and CO2 Emissions, ICCT, October 2009 57 SAE 2006 - 01 - 3456 58 U.S. EPA. Heavy - Duty Coastdow n Test Procedure Development. Docket # EPA - HQ - OAR - 2010 - 0162 - 0144. 59 ICF. Investigation of Costs for Strategies to Reduce Greenhouse Gas Emissions fro m Heavy - Duty On - Road Vehicles. July 2010. Docket Identification Number EPA - HQ - OAR - 2010 - 0162 - 0044. 60 21 st Century Truck Partnership, “Roadmap and technical White Papers”, U.S. Department of Energy, Technical paper: 21CTP - 0003, December 2006. 61 “T ires & Truck Fuel Economy,” A New Perspective. Bridgestone Firestone, North American Tire, LLC, Special Edition Four, 2008. 62 “Michelin’s Green Meters,” Press Kit, October, 30, 2007. http://www.michelin - green meter.com/main.php?cLang=en (Com plete Press File, Viewed March 6, 2010) 63 “Modeling of Fuel Consumption for Heavy - Duty Trucks and the Impact of Tire Rolling Resistance,” Tim J. LaClair, Russell Truemner, SAE International, 2005 - 01 - 3550, 2005. 64 “Modeling of Fuel Consumption for Heavy - Duty Trucks and the Impact of Tire Rolling Resistance,” Tim J. LaClair, Russell Truemner, SAE International, 2005 - 01 - 3550, 2005.**Regulatory Impact Anal ysis** 

2 - 124 65 “Factors Affecting Truck Fuel Economy,” Goodyear, Radial Truck and Retread Service Manual. Accessed February 16, 2010 at http://www.goodyear.com/truck/pdf/radialretserv/Retread_S9_V.pdf . 66 “T ire Rolling Resistance, Its Impact on Fuel Economy, and Measurement Standards,” Presentation by Tim J. LaClair of Michelin Americas Research & Development Corp. to the Cali fornia Energy Commission, 2002. 67 “T echnology Roadmap for the 21 st Century Truck Program. A Government - Industry Partnership,” U.S. Department of Energy, 21CT - 001, December 2000. 68 “Energy Efficiency Strategies for Freight Trucking: Potential Impact on Fue l Use and Greenhouse Gas Emissions,” J. Ang - Olson, W. Schroer, Transportation Research Record: Journal of the Transportation Research Board, 2002(1815):11 - 18. 69 “Effect of Single Wide Tires and Trailer Aerodynamics on Fuel Economy and NOx Emissions of Cla ss 8 Line - Haul Tractor - Trailer,” J. Bachman, A. Erb, C. Bynum, U.S. Environmental Protection Agency, SAE International, Paper Number 05CV - 45, 2005. 70 “Class 8 Heavy Truck Duty Cycle Project Final Report,” U.S. Department of Energy, Oak Ridge National Labo ratory, ORNL/TM - 2008/122, p. 21, December 2008. Accessed January 19, 2010 at http://cta.ornl.gov/cta/Publications/Reports/ORNL_TM_2008 - 122.pdf . 71 “Are Ultra - Wide, Ultra - Lo w As pect Ratio Tires the Next Big Thing?” K. Rohlwing, Today’s Tire Industry, Vol. 1, Issue 1, July/August, July 2003. 72 “New Generation Wide Base Single Tires,” American Trucking Association, White paper presented at the International Workshop on the use of w ide tires sponsored by Federal Highway Administration, Turner - Fairbank Highway Research Center, October 25 - 26, 2007, Revision 9, December 21, 2007, Accessed on February 3, 2010 at http://www.arc.unr.edu/Workshops/Wide_Tires/Wide_Base_Summary - v9 - AT A - whitepaper.pdf 73 “Recommended Practice: Guidelines for Outset Wide Base Wheels for Drive, Trailer and Auxiliary Axle Applications (Draft),” Technology and Maintenance Council, Council of American Trucking Associations, circulated September 28, 2009. 74 ICF. Inve stigation of Costs for Strategies to Reduce Greenhouse Gas Emissions fro Heavy - Duty On - Road Vehicles. July 2010. Docket Identification Number EPA - HQ - OAR - 2010 - 0162 - 0044. 78 “SmartWay Transport Partnership: Innovative Carrier Strategies”, February 2004, EPA420 - F - 04 - 005, A ccessed on the Internet on January 18 , 2010 at: http://www.epa.gov/smartway/transport/what - smartway/carrier strategies.htm#weight . 79 Aluminum report http://aluminumintransportation.org/downloads/info_kit/2011RicardoCVStudy.pdf 80 “Energy Savings through Increased Fuel Economy for Heavy Duty Trucks”, The rese Langer, American Council for an Energy - Efficient Economy prepared for the National Commission on Energy Policy, February 11, 2004. 81 “Best practices Guidebook for Greenhouse Gas Reductions in Freight Transportation”, H. Christopher Fey, Po - Yao Kuo, North Carolina State University prepared for the U.S. Department of Transportation, October 4, 2007.

82 21 st Century Truck Partnership, “Roadmap and technical White Papers”, U.S. Department of Energy, Technical paper: 21CTP - 0003, December 2006, 83 “Reducing heavy - Duty long haul Combination Truck Fuel Consumption and CO2 Emissions”, NESCCAF, ICCT, SwRI, TIAX LLC, October 2009.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 125 84 “T he Potential Effect of Future Energy - Efficiency and Emissions - Im proving Technologies on Fuel Consumption of Heavy Trucks”, Argonne National Laboratory, Technical Report ANL/ESD/02 - 4, August 2002. 85 U.S. EPA. http://www.epa.gov/smartway/documents/weightreduction.pdf 86 Alcoa. “Improving Sustainability of Transport: Aluminum is Part of the Solution.” 2009 87 Schutte, Carol. U.S. Department of Energy, Vehicle Technologies Program. “Losing Weight

– an enabler for a Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light - Duty Vehicles” 88 American Iron and Steel Institute. “A Cost Benefit Analysis Report to the North American Steel Industry on Im proved Materials and Powertrain Architectures for 21st Century Trucks.” 89 Schutte, Carol. U.S. Department of Energy , Vehicle Technologies Program. “Losing Weight

– an enabler for a Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light - Duty Vehicles” 90 Schutte, Caro l. U.S. Department of Energy, Vehicle Technologies Program. “Losing Weight

– an enabler for a Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light - Duty Vehicles” 91 Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use by Idling Commercial Trucks. 2006. Page 9. 92 Gaines, L. and D. Santini. Argonne National Laboratory, Economic Analysis of Commercial Idling Reduction Technologies 93 Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use by Idling Commercial Trucks. 2006. Page 9. 94 Kahn,AB, M, N. Clark, G. Thompson, W.S. Wayne, M. Gautam, and D. Lyons. Idle Emissions from Heavy Duty Diesel Vehicles: Review and Recent Data. 2006. Journal of A ir and Waste Management Association. Page 1416. 95 Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use by Idling Commercial Trucks. 2006. Page 7. 96 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 124. 97 Gaines, L., A. Vyas, J. Anderson. Estimation of Fuel Use by Idling Commercial Trucks. 2006. Page 6. 98 Brodrick, C., T.Lipman, M. Farshchi, H. Dwyer, S. Gouse III, D.B. Harris, and F.King, Jr. Potenti al Benefits of Utilizing Fuel Cell Auxiliary Power Units in Lieu of Heavy - Duty Truck Engine Idling. 2001. Page 3. 99 Lim, Han. Study of Exhaust Emissions from Idling Heavy - Duty Diesel Trucks and Commercially Available Idle - Reducing Devices. EPA420 - R - 02 - 052. 2002. Page 2. 100 Kahn,ABM, N. Clark, G. Thompson, W.S. Wayne, M. Gautam, and D. Lyons. Idle Emissions from Heavy Duty Diesel Vehicles: Review and Recent Data. 2006. Journal of Air and Waste Management Association. Page 1405.**Regulatory Impact Anal ysis** 

2 - 126 101 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. 2010. Page 122 says the best in class APU consumes 0.18 gallon per hour. 102 National Academy of Science. Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles. March 2010. Page 124. 103 See Title 13, California Code of Regulations § 1956.8, Requirements to Reduce Idling Emissions From New and In - Use Trucks , available at http://www.arb.ca.gov/regact/hdvidle/frorev.pdf 104 See http://www.osha.gov/SLTC/trucking_industry/index.html and http://www.fmcsa.dot.gov/rules regulations/administration/fmcsr/fmcsrruletext.aspx?reg=393.76 , accessed May 2011 105 See http://www.ccohs.ca/oshanswers/ phys_agents/heat_health.html , and http://www.coolantarctica.com/Antarctica%20fact%20file/science/cold_humans.htm, accessed May 2011 106 Data Collected by the Texas Transportation Institute as part of NTRD Project N - 42: Development of a NOx Verification Prot ocol and Actual Testing of Onboard Idle Reduction Technologies. Sponsored by Houston Area Research Council (HARC) and US EPA SmartWay Transport Program. May 2011 107 See http://www.leonardbus.com/PageZoneSiteResources/LeonardBus.com/Resources/file/PDF_info/MX7%20Cold %20Starting.pdf

; and https://evalu e.internationaldelivers.com/service/bodybuilder/general/engine_feature/documents/NAVI_910DT_ CAP_021211_MY2010_REV1.pdf , accessed May 2011 108 American Trucking Association. Last viewed on January 29, 2010 at http://www.trucksdeliver.org/recommendations/speed - limits.html 109 U.S. EPA SmartWay Transport Partnership. Last viewed on January 28, 2010 at http://www.epa.gov/smartway/transport/document s/tech/reducedspeed.pdf 110 Department for Transport, Vehicle and Operator Services Agency. Last viewed on January 6, 2010 at http://www.dft.gov.uk/vosa/newsandevents/pressreleases/2006pressreleases/28 - 12 - 06speedlimiterlegislation.htm 111 Transport Canada. Summary Report

– Assessment of a Heavy Truck Speed Limiter Requirement in Canada. Last viewed on January 6, 2010 at http://www.tc.gc.ca/eng/roadsafety/tp - tp14808 - menu - 370.htm 112 Transport Canada. Summary Report

– Assessment of a Heavy - Truck Speed Limiter Requirement in Canada. 113 “Assessment of Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles”, TIAX LLC, November 19, 2009. Page 4 - 98. 114 “Assessment of Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles”, TIAX LLC, November 19, 2009. Page 4 - 98. 115 NESCCAF/ICCT. “Reducing Heavy - Duty Long Haul Combination Truck Fuel Consumption and CO 2 Emissions . ” October, 2009] 116 US Environmental Protection Agency's SmartWay Transport Partnership July 2010 e - update accessed July 16, 2010, from http://www.epa.gov/smartwaylogistics/newsroom/documents/e - update - july - 10.pdf 117 NAS Report. Page 146. 118 TIAX. Assessment of Fuel Economy Technologies for Medium - and Heavy - D uty Vehicles. November 2009. Page 4 - 40.***** E.O. 12866 Review –**  **Draft –**  **Do Not Cite, Quote, or Release During Review *****

2 - 127 119 As explained further in Section V below , EPA would use these inputs in GEM even for engines electing to use the alternative engine standard. 122 See Docket EPA - HQ - OAR - 2010 - 0162 123 Se e 75 FR at 74244. 124 See comments to docket EPA - HQ - OAR - 2010 - 0162 - 1761; Ford Motor Company 125 The agency notes the highest RRC values recorded for LT tires, of 11.0 and 10.9, were for two tires of the same size and brand. The nearest recorded values to these two tires were 9.8; substantially beyond the differences between other tires tested. 126 Kargul, J. J., 2010, "Clean Automotive Technology. Cost - Effective Solutions for a Petroleum and Carbon Constrained World," Presentation made to National Academy of Scie nces, Revie w of 21st Century Truck Program, September 8, 2010 127 “Best practices Guidebook for Greenhouse Gas Reductions in Freight Transportation”, H. Christopher Fey, Po - Yao Kuo, North Carolina State University prepared for the U.S. Department of Transportation, October 4, 2007. 128 “Reducing Heavy - Duty long haul Combination Truck Fuel Consumption and CO2 Emissions”, NESCCAF, ICCT, SwRI, TIAX LLC, October 2009. 129 The U.S. EPA has reclamation requirements for refrigerants in place under Title VI of the Clean Air Act. 130 The global warming potentials (GWP) used in the NPRM analysis are consistent with Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). At this time, the IPCC Second Assessment Report (SAR) global warming potential values have been agreed upon as the official U.S. framework for addressing climate change. The IPCC SAR GWP values are used in the official U.S. greenhouse gas inventory submission to the climate change frame wo rk. When inventories are recalculated for the final rule, changes in GWP used may lead to adjustments. 131 Schwarz, W., Harnisch, J. 2003. “Establishing Leakage Rates of Mobile Air Conditioners.” Prepared for the European Commission (DG Environment), Doc B4 - 3040/2002/337136/MAR/C1. 132 Vincent, R., Cleary, K., Ayala, A., Corey, R. 2004. “Emissions of HFC - 134a from Light - Duty Vehicles in California.” SAE 2004 - 01 - 2256. 133 The Minnesota refrigerant leakage data can be found at http://www.pca.state.mn.us/climatechange/mobileair.html#leakdata. 134 Society of Automotive Engineers, “IMAC Team 1

– Refrigerant Leakage Reduction, Final Report to Sponsors,” 2006. 135 Society of Automotive Engineers Surface Vehicle Standard J2727, issued August 2008, http://www.sae.org. 136 “Review of Low Carbon Technologies for Heavy Goods Vehicles

– Annex 1”, Ricardo prepared for Department of Transport, Technology Paper RD.09/182601.7, Jun 2009 137 U.S. Environmental Protection Agency Office o f Transportation and Air Quality SmartWay Transport Partnership, A Glance at Clean Freight Strategies: Drivers Training EPA 420 - F - 04 - 008; February 2004. 138 Ibid.**Regulatory Impact Anal ysis** 

2 - 128 139 National Research Council, Technologies and Approaches to Reducing the Fuel Consumption of Me dium and Heavy - Duty Vehicles, Committee to Assess Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles; Washington, DC, National Academies Press, 2010. 140 Information from US EPA review of 2009 SmartWay Excellence Awards applications. 141 U.S. Envir onmental Protection Agency Office of Transportation and Air Quality SmartWay Transport Partnership, A Glance at Clean Freight Strategies: Drivers Training EPA 420 - F - 04 - 008; February 2004. 142 “Buses & Retread Tires,” The Tire Retread & Repair Information B ureau, Pacific Grove, Ca., Accessed on January 27, 2010 at http://www.retread.org/packet/index.cfm/ID/284.htm. 143 “What are Retreaders Doing to Improve Fuel Efficiency?” H. Inman, Tire Review , December 11, 2006, Accessed on February 18, 2010 at http://www.tirereview.com/Article/59777/what_are_retreaders_doing_to_improve_fuel_efficiency.aspx . 144 “Better Fuel Economy? Start with a Strong Tire Progr am ,” H. Inman, Fleet & Tire 2006, Tire Review , December 11, 2006, Accessed on February 18, 2010 at http://www.tirereview.com/Article/59776/better_f uel_economy_start_with_a_strong_tire_program.aspx . 145 National Research Council, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles, Committee to Assess Fuel Economy Technologies for Medium - and Heavy - Duty V ehicles; Washington, DC, National Academies Press, 2010. 146 Technology and Maintenance Council of the American Trucking Associations, Tire Air Pressure Study, Tire Debris Prevention Task Force S.2 Tire & Wheel Study Group; May 2002 . 147 “Co mmercial Vehicle Tire Condition Sensors,” Federal Motor Carrier Safety Administration. Report No. FMCSA - PSV - 04 - 002, November 2003. 148 National Research Council, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehic les, Committee to Assess Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles; Washington, DC, National Academies Press, 2010. 149 U.S. Environmental Protection Agency Office of Transportation and Air Quality SmartWay Transport Partnership, A Glance at Clean Freight Strategies: Automatic Tire Inflation Systems EPA 420 - F - 04 - 0010; February 2004. 150 National Research Council, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles, Committee to Assess Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles; Washington, DC, National Academies Press, 2010. 151 Ibid. 152 “Co mprehensive Truck Weight and Size Study: Summary Report,” U.S. DOT Federal Highway Traffic Administration, August 2000. 153 “Co mprehensive Truck Weight and Size Study: Summary Report,” U.S. DOT Federal Highway Traffic Administration, August 2000. 154 U.S. Department of Transportation. “Comprehensive Truck Size and Weight Study,” Volume 3. August 2000. 155 “Co mprehensive Truck Weight and Size Study: Summary Report,” U.S. DOT Federal Highway Traffic Administration, August 2000. 156 National Research Council, Technologies and Approaches to Reducing the Fuel Consumption of Medium and Heavy - Duty Vehicles, Commi ttee to Assess Fuel Economy Technologies for Medium - and Heavy - Duty Vehicles; Washington, DC, National Academies Press, 2010.