American Council for an Energy-Efficient Economy ● Environmental Defense Fund 

● Natural Resources Defense Council ● Northeast States for Coordinated Air Use 

Management ● Sierra Club ● Union of Concerned Scientists 

Key Opportunities to Strengthen Proposed Medium- & HeavyDuty Truck Standards 

Our organizations commend EPA and NHTSA for releasing the Notice of Proposed 

Rulemaking (NPRM) to establish fuel efficiency and greenhouse gas standards for new 

medium- and heavy-duty trucks sold in model years 2014 to 2018. Setting the first-ever 

standards for these vehicles is an important part of meeting the President’s commitment 

to reduce America’s oil dependence and cut greenhouse gas emissions from the 

transportation sector. 

While the proposed standards represent a step forward, we urge the agencies to make 

critical improvements before finalizing the standards in order to improve the program’s 

efficacy in the short-term and to establish a strong foundation for future rulemakings. 

Our organizations appreciated the opportunity to recommend these improvements in 

testimony given during the recent public hearings and will provide more technical details 

in our written submissions to the docket. 

Overall, it is critical that the agencies finalize strong standards for trucks that achieve the 

greatest possible fuel savings and greenhouse gas reductions. The technology exists to 

set more stringent standards in the model year 2014-2018 timeframe for all classes of 

trucks. Specifically, trailer improvements offer a tremendous opportunity to increase fuel 

efficiency and reduce emissions and should be subject to standards starting in model year 

2014. In addition, this rulemaking must establish a strong foundation for future truck 

standards that are based on full-vehicle testing. 

Beyond these overarching improvements, we provide six specific recommendations to 

strengthen the final rule by modifying existing elements of the proposed standards and 

adding new provisions: 

 

1. Establish a Pathway to a Mature Program; Ensure Adequate Data Collection and 

Transparency: The agencies should design the rule to transition from a 

technology/component-based approach to a performance-based vehicle standard by 2018. 

This will involve rapid development of duty-cycle-specific test protocols and standards. 

To achieve this and to ensure transparency, the program needs to include a major data 

collection component from the outset, including i) in-use testing and full vehicle testing 

data from manufacturers and government agencies; ii) manufacturer reporting of actual 

configurations sold and their simulated fuel consumption; and iii) the status of 

manufacturer compliance including credit balances for each compliance category. The 

agencies should make the collected data public and provide annual reports describing 

new and on-road fleet performance.

2. Increase the Stringency for Class 2B and 3 Pick-ups and Vans: The standards should 

be accelerated to achieve the proposed 2018 requirements by 2016 in order to be 
consistent with the 2012-2016 light-duty rule. For gasoline picks-up and vans, the 

standards should be strengthened to achieve at least a 15 percent reduction by 2018. 

3. Increase the Stringency for Vocational Trucks: The vocational truck emissions 

reduction requirement should be at least 6 percentage points greater than currently 

proposed for medium-duty vocational trucks and 3 percentage points greater for heavyduty vocational trucks in 2017, reflecting the potential for savings from hybridization, 

advanced transmissions, weight reduction, and other efficiency improvements. This 

modest increase in the stringency of the proposed standards, along with refinements to 

the protocols for demonstrating innovative technology benefits, will encourage 

improvements beyond engines and tires and result in greater overall emission reductions 

and fuel savings. 

4. Incentivize Advanced Technologies: The program needs to provide greater incentive 

for advanced technologies and other efficiency improvements that are not necessary to 

meet the standards as proposed. To that end, the agencies should i) further develop the 

supplemental powerpack testing options and ensure they are applicable to a range of 

technologies, and ii) increase the stringency of the vocational standards (as in item 3) to 

ensure that advanced technology credits have value in the marketplace. 

5. Establish a Long-Term Trajectory for Engine Standards: The rule needs to provide 

enough information on the trajectory of engine standards to ensure sustained investment 

in next generation engine technologies. In the final preamble, EPA should include a 2020 

target for stringency in each engine category based on technologies identified by the 

National Academy of Sciences (NAS) available over this time period. 

6. Require Fuel Economy Labels for Trucks: Labels should allow truck buyers, and, in 

particular used truck buyers, to better compare the fuel efficiency performance of the 

trucks they are considering. Heavy-duty pickups and vans should display fuel 

consumption on a consumer label. For larger vehicles and their engines, a permanent 

label should show estimates of fuel use over a few key cycles, analogous to city and 

highway MPG for light-duty vehicles. Research previously submitted to EPA shows how 

truck fuel use over a small number of cycles can be used to predict fuel use on a wide 

range of duty-cycles. 
1. Adequate Data Collection and Transparency 

Overview

In the proposed rule, DOT/EPA discuss the need for a new, more sophisticated approach 

to vehicle testing than currently proposed to “completely capture the complex 

interactions of the total vehicle and the potential to reduce fuel consumption and GHG 

emissions through the optimization of those interactions.” (75 Fed. Reg. at 74172) 

The Heavy-duty National Program should transition to a compliance scheme based on 

actual technology performance in a full-vehicle configuration. Doing so will enable 

future standards to encourage technologies that fail to be differentiated in the current 

compliance regime but can actually cut emissions and fuel consumption. To enable the 

transition, the agencies should include requirements in this rule to collect and publicly 

disseminate existing vehicle performance data and data generated in future model years. 

The agencies should also establish procedures to demonstrate progress and to enhance the 

program transparency. 

Comments/Concerns

Requirements for public data are intended to accomplish three goals: 

(a) Establish a broad technical database to support transition of the compliance 

regime from one based on simulation results of specific components to one based 

on full-vehicle technology implementation and testing that is validated by on-road 

measurements, 

(b) Enhance public understanding of actual technology adoption, and 

(c) Track actual on-road emissions and fuel consumption performance of new 

vehicles and the full on-road fleet. 

Proposed Solutions

1. Collect in-use testing and full vehicle testing data performed by manufacturers 

and the federal agencies. Expand agency on-road testing to validate current 

compliance models and encourage manufacturers to provide more data. Make 

data publicly available. 

2. Require manufacturers to report actual specifications for vehicle configurations 

sold. Run GEM using these specifications. 

3. Build a truck market database for public use and evaluation. Include a description 

of the truck fleet population and its operating characteristics through data types 

previously provided through the U.S. Census Vehicle Inventory and Use Survey 

but also organize data consistent with the subcategories used in the truck 

emissions and fuel economy compliance regime. 

4. Publish an annual report describing new and on-road fleet performance. For new 

vehicles, the report should contain data similar to EPA’s annual publication of 

“Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel 

Economy Trends.” The report should be expanded to cover performance and 

summary characteristics (from the database described in section 3 above) of the 

existing fleet so an overall picture of medium- and heavy-duty truck emissions 

and fuel consumption progress is clear. 

5. Publish an annual report describing manufacturer credit balances within each 

compliance category and the use of any credit flexibility mechanisms, such as 

advanced technology credits. 
2. Stringency for Class 2B and 3 Pickups and Vans 

Overview

For heavy-duty pickup trucks and vans, the agencies propose a 10 percent and 14 percent 

reduction in CO2 emissions from 2010 levels from gasoline and diesel fueled vehicles, 

respectively, in 2018. For gasoline vehicles, they consider a technology package 

combining low friction lubricants, reduction of engine friction loss, stoichiometric 

gasoline direct injection (S-GDI), automatic 6- and 8-speed transmissions, low rolling 

resistance, 5 percent mass reduction, and improved aerodynamics. The agencies estimate 

CO2 emissions reductions of 10 percent and a cost of about $1,368 for this package, 

leading to a 5-year payback. (75 Fed. Reg. 74234-74239) 

Comments/Concerns

AEO 2010 projects that heavy-duty pickups and vans will already achieve virtually the 

same efficiency in the Reference Case as the proposed standard requires, because these 

vehicles will take advantage of the technologies brought to market by the 2012-2016 

light-duty rule. Therefore, to accelerate that take-up, the standard for heavy pickups and 

vans should require the proposed improvements by 2016. 

In the proposed package, the agencies did not include technologies like cylinder 

deactivation and coupled cam phasing, which in their own assessment are cheap (together 

costing less than $250) but effective, reducing CO2 by 4 to 8 percent. Adding these two 

technologies to the agencies’ proposed package would provide a reduction of 15 percent, 

according to EPA’s Lumped Parameter Model. The revised package offers a payback in 

less than 4 years, which is less than the payback period for the agencies’ original package 

achieving only 10 percent savings. 

Furthermore, the proposed standard does not take advantage of other promising 

technologies including Turbo-GDI, which combines S-GDI, turbocharging, and 

downsizing for gasoline vehicles. According to the TIAX 2009 report submitted to the 

NAS, this package will reduce CO2 emissions for large trucks by 11 to 17 percent 

compared to stoichiometric GDI. The technologies have an added cost of $2,000-$3,000, 

but the payback period for these technologies on top of the agencies’ proposed package is 

5 years. The 2010 NAS study also estimated a 10 to 14 percent reduction potential for 

CO2 from turbocharged downsized direct injection engine with Variable Valve Actuation 

(VVA). 

Proposed Solutions

1. Accelerate phase-in of the gasoline and diesel standards for heavy-duty pickups 

and vans to achieve the proposed 2018 requirements by 2016. 

2. For gasoline pickups and vans, strengthen standard to achieve at least 15 percent 

reduction by 2018 by including cylinder deactivation and coupled cam phasing in 

the proposed package. 

3. Consider other promising technologies including Turbo-GDI and VVA that have 

the potential to significantly reduce CO2 emissions and provide a reasonable 

payback period. 
3. Stringency for Vocational Trucks 

Overview

The proposed standards for vocational trucks would bring 1 to 2 percent savings beyond 

what is gained through engine efficiency improvements. This reflects the benefits of low 

rolling resistance tires alone. Other potential vehicle improvements, including 

aerodynamics and mass reduction, cannot be captured by the proposed regulations 

because the regulated entities are the chassis manufacturers, and the regulated vehicle has 

a standard body by assumption. Similarly, gearing and transmission selection are not 

captured by the standard. Manufacturers may obtain credit for transmission 

improvements and other “innovative” technologies if they can demonstrate the savings 

from these technologies to the satisfaction of the EPA. Credits are also available for 

hybrids and other “advanced” technologies. 

 

Comments/Concerns

The NAS report explored savings opportunities beyond engine and tires for vocational 

vehicles, including hybridization, aerodynamic improvements, advanced transmission, 

and mass reduction. For transmissions, for example, the NAS found savings in the range 

of 2 to 8 percent. 

Significant penetration of hybrids is anticipated in the vocational sector. For example, 

Pike Research projects 300,000 medium- and heavy-duty hybrid sales, or 7 percent of 

projected sales, by 2015.1

 Furthermore, at least one transmission manufacturer is 

claiming savings of more than 8 percent for vocational trucks on average using 

automated manual or dual clutch transmissions to replace the torque converter automatics 

that now dominate the market. Assuming two percent savings on average from 

hybridization across vocational trucks along with other savings consistent with NAS, 

additional savings (beyond those from tires) on the order of 12 percent for medium and 7 

percent for heavy vocational vehicles will be achievable by 2017. 

To a large degree, the gap between the agencies’ proposed standards and what others 

have concluded is possible to achieve reflects the constraints of the rule structure and 

testing protocol for vocational trucks, rather than a difference in views of technological 

potential. The proposal to allow credit for “advanced” and “innovative” technologies 

could help to bridge this gap, but only if the protocols for gaining credit are well defined 

and the vocational standard is strong enough to provide manufacturers with an incentive 

to adopt these technologies. 

Proposed Solutions

1. Establish specific test protocols for crediting of advanced transmissions and other 

efficiency technologies. 

2. Require vocational trucks to reduce emissions by at least an additional 6 percent 

for light and medium vehicles and an additional 3 percent for heavy vehicles by 

2017 (a total of 12 percent and 7 percent, respectively), promoting the production 

of hybrids and the faster uptake of advanced technologies. 

 

1

 Pike Research http://greenbigtruck.com/2010/06/pike-research-forecasts-300000-medium-heavy-duty-hybrids-by-2015; AEO 2010. 
4. Incentivizing Advanced Technologies

Overview

EPA and NHTSA have proposed a crediting system to incentivize the adoption of certain 

advanced vehicle technologies. As proposed, manufacturers would receive special 

Advanced Technology Credits for hybrid vehicles, Rankine (bottoming) cycle engines, 

all-electric vehicles, and fuel cell vehicles. Unlike credits generated by ‘conventional’ 

engines and vehicles, these advanced technology credits would be transferable to any of 

the seventeen regulatory subcategories for both engines and vehicles. 

Comments/Concerns

Transmissions. In its current form, the GEM software does not quantify the impact of 

transmission technologies. The NAS reported that advances in transmission systems 

represented a potential 3 to 7 percent reduction in fuel consumption, depending on the 

vehicle category in the 2015-2020 timeframe. 

Hybrid vehicle test procedure. There are currently three options for testing the benefits of 

hybrid vehicles as compared to their conventional counterparts. The first option is to test 

entire vehicles using a chassis dynamometer and a designated test cycle. The second and 

third option are to use an engine or “powertrain” dynamometer to conduct “hardware-inthe-loop” testing of the complete hybrid powertrain, including the engine and all hybrid 

system components. Option 2 can be used to test only pre-transmission hybrid systems, 

while Option 3 can be used to test any pre-transmission or post-transmission hybrid 

system. Option 3 could also be used to test other advanced power train technologies such 

as continuously variable transmissions (CVT) and automated manual transmissions 

(AMT). 

Sufficient incentive for advanced technologies. The stringency level in the program 

must be strong enough to drive accelerated penetration of advanced technology. Also, in 

addition to cross-category trading, the agencies are requesting comment as to whether a 

multiplier of 1.5 for these credits would be appropriate for further incentivizing the 

introduction of advanced technologies. It is not clear that these additional credits would 

be redeemable, given the modest stringency levels set forth in the proposal—especially in 

the case of vocational vehicles where the potential is greatest for technologies such as 

hybrids and electric vehicles. As such, multiplier values should not be used at this time. 

Proposed Solutions

1. To catalyze further development in transmission and hybrid technologies, develop a 

chassis and/or ‘post-transmission’ testing procedure that could better capture the 

benefits of a host of driveline-related improvements including AMT, CVT, and 

hybrid technologies. 

2. For hybrid test procedure, adopt chassis testing or hardware-in-the-loop powertrain 

testing using the same test cycles and cycle weightings as proposed for chassis 

testing. However, if engine or powertrain testing is allowed for certifying pretransmission hybrids, the agencies must define negative torques in the motoring 

sections of the FTP to represent recharging events such as braking or downhill 

driving. 

3. In the longer term, move towards harmonization of engine and chassis cycles, with a 

reduced dependence on the FTP cycle. 
5. Engine Standards - Trajectory for 2020 

Overview

Engine standards for medium- and heavy-duty vehicles should be designed to maximize 

fuel savings and spur investment in next generation technologies. The proposed 

standards establish two phases of medium- and heavy-duty engine emissions and fuel 

consumption stringency levels beginning in model year 2014 and model year 2017. The 

stringency levels are based on an assessment of engine-related technologies that are 

currently available today. Additional technologies not captured by the standards are 

identified but are not evaluated for their potential impact on future engine standards. 

Comments/Concerns

There are technologies under development, such as advanced waste heat recovery, that 

could improve engine performance beyond the levels required in the proposed standards. 

These technologies will require significant levels of investment to reach full 

commercialization by 2020. A strong indication of the direction of future standards 

would help ensure these advanced engine technologies are ready in the post-2017 

timeframe. 

Forthcoming technologies could provide major efficiency gains by 2020. The National 

Academies of Science identified engine technologies that would allow heavy-duty tractor 

engines to achieve a 13 percent to 17 percent reduction in fuel consumption by 2020, 

compared to a 2010 engine. These technologies are in many cases being advanced 

through the SuperTruck program. In comparison, the proposal calls for a 6 percent 

reduction in fuel consumption by 2017. 

The proposed engine standards will improve fuel consumption by requiring the use of 

off-the-shelf technology, but further advances in engine technology will require greater 

incentives. Laying out a technical roadmap and stringency target for engine 

improvements that go beyond 2017 would provide technology developers an indication 

of the future direction of the standards and encourage further investment, development, 

and deployment of these technologies. 

Proposed Solution

EPA should include in the final preamble a 2020 target for stringency in each engine 

category based on an evaluation of technologies identified by the National Academy of 

Sciences expected over this time period. 
6. Labeling 

Overview

Labeling requirements in the proposed rule are as follows: 

• For Class 2B and Class 3 pickups, the label would show compliance with criteria 

pollutant standards only. (75 Fed. Reg. at 74263) 

• For engines, the current label for criteria pollutants is permanent and provides 

descriptive information, including displacement, emission control systems, and 

tune-up specifications. Under this rule, the label would also indicate whether the 

engine is certified for tractor or vocational use and, if the manufacturer is using 

ABT, the Family Emissions Limit. (75 Fed. Reg. at 74268) 

• For tractor trailers, the label would include descriptive information about the 

vehicle and its certified engine, and about any features that would affect GHG 

emissions such as aerodynamic equipment and tires. It would also list the 

vehicle’s Family Emissions Limit for GHG if the manufacturer is using ABT. 

• Vocational trucks would be labeled similarly to tractors. Aerodynamic equipment 

would not be included, but hybrid powertrain or other advanced technology 

applied to the certification of the vehicle would be. 

The agencies decline to require fuel consumption labeling, because they believe it could 

mislead the purchaser. (75 Fed. Reg. at 74352) 

Comments/Concerns

The label should serve not only as a compliance tool, but also to provide consumer 

information. Lack of standardized fuel consumption information is a market barrier to 

efficient technologies. For heavy pickups and vans, a label similar to the light-duty 

vehicle label would be appropriate. 

For engines, tractors, and vocational trucks, the Family Emissions Limit, at a minimum, 

should be provided on the label, whether or not the manufacturer is participating in ABT. 

While such information may not at this stage allow for meaningful estimates of on-road 

fuel consumption, it should allow comparisons across similar vehicles and promote the 

deployment of efficiency technologies. For vocational vehicles, labels showing 

performance on each of the drive cycles (transient, 55 mph, 65 mph) would allow users to 

better understand the suitability of a given vehicle for their duty cycles. 

Proposed Solutions

1. Class 2bs should be labeled with fuel consumption in gallons per 100 miles. Fuel 

consumption could be supplemented with payload and towing capacity 

information on the label. 

2. Engine, tractor, and vocational truck labels should include the Family Emissions 

Limit, regardless of whether the manufacturer is participating in ABT. 

3. Tractor and vocational truck labels should list the vehicle’s (or family’s) 

performance on each cycle test cycle, instead of, or in addition to, the weighted 

average used for certification.