1 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

NATIONAL VEHICLE AND FUEL EMISSIONS LABORATORY

2000 TRAVERWOOD DRIVE ANN ARBOR, MI 48105

- 2498

OFFICE OF
AIR AND RADIATION February 12 , 201 6

MEMORANDUM

SUBJECT: Vocational Vehicle Technology Packages for Custom Chassis

FROM: Lauren Steele, Environmental Engineer, OTAQ/ASD

TO: Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium

and Heavy

- Duty Engines and Vehicles

- Phase 2

- Docket EPA

- HQ

- OAR

- 2014

- 0827

I ntroduction

This me mo randum describes technology packages developed for select vocational
vehicles manufactured as custom chassis. The agencies requested comment on whether to develop separate standards for these, though we did not propose to do so. T he agencies received comments indicating that, for manufacturers unable to use emission averaging, the primary vocational vehicle standards were not feasible for some types of vehicles, thus in response, a specific technical feasibility analysis has been cond ucted for vehicles in seve n vocations.

Definit ion s

While we did not propose a definition of what would qualify as a custom vocational vehicle, we requested comment on this. Based on th e information available, we believe that a
reasonable definition could be a vehicle whose final intended build can be attested by the chassis manufacturer to be one of the seven vehicle types listed in Table 1. If a chassis may be finished into one of the vehicle types listed, but the certi fying manufacturer is unable to know this

, or unable to establish controls to ensure this at the time of certification, then it would not be a
custom vocational vehicle.

The selection of specific vocations for this analysis has been informed by business
i nformation about chassis manufacturers who have certified to the Phase 1 standards, public comments, and other stakeholder outreach. The agencies have listed in Table 1 some attributes
that may be used to distinguish custom chassis from other vocational v ehicles. Conversations are ongoing regarding identifiable attributes of small transit and shuttle buses in weight classes
2b

- 5. We are also considering aligning our defined attributes with those of NHTSA , which has2

recently adopted a rule requiring seat b elts on “over

- the

- road” buses, 1 meaning those characterized by an elevated passenger deck located over a baggage compartment, as well as buses having a GVWR of 11,793 kg (26,000 lb) or greater, except school buses, urban transit buses, and some others.

Ta ble 1 : Custom Chassis Types
Vehicle Type Potentially Distinguishable Features Coach (Intercity)
Bus Front doors only, no standing passengers , high

- backed seats, possibly

restroom facilities

, luggage compartment , no onboard fare

- collection
Transit Bus Both front and center doors, low

- back seating, passenger stop

- request

system, possibly rear engine, low floors, standing passenger positions, wheelchair lifts, onboard fare

- collection

Motor Home (recreational vehicle) Primary purpose is temporary housing; both propulsion engine and

sleeping quarters

School Bus Primary purpose is pupil transport
Refuse Truck Low cab forward, p rimary purpose is collection of solid waste
Cement Mixer Primary purpose is delivery of freshly mixe d concrete Emergency Vehicle Fire truck or ambulance, defined at 40 CFR 86.1803

Industry Characterization

Based on public comments, information on entities who have certified, and stakeholder outreach, we have compiled an illustrat ion of the level of diversi fication of the vocational vehicle manufacturers supplying these seven vocations in Table 2. This table is not intended to be exhaustive, rather illustrate that there are several manufacturers who are not diversified in their products, who are compe ting for sales with diversified manufacturers. Based on the definition above, it would be likely that the single

- type (non

- diversified) manufacturers would be able to certify their products as custom vocational vehicles, while only some of the multiple

- typ e manufacturers (diversified) would have sufficient knowledge about , or control over, the intended use of their products to certify one or more types as custom vocational vehicles.

Table 2 : Diversification of Vocational Chassis Manufacturers a
Vehicle Type Number of Single

- type Chassis Manufacturers Number of Multiple

- type Chassis Manufacturers Coach (Intercity) Bus 2 3

Motor Home 3 8
School Bus 1 2
Transit Bus 4 4
Refuse Truck 1 6
Cement Mixer 2 7 Emergency Vehicle 6 7

a Includes U

. S

. - made vehicle s and those imported for sale in the U

. S

.

1 See Occupant Crash Protection rule, November 25, 2013, 78 FR 70415, 49 CFR 571, FMVSS 2083

Structure of Phase 2 Program

Based on public comment and stakeholder outreach, the following approach has been developed. For any model year of the Phase 2 program , a manufacturer of one or more vocational chassis certified as custom vocational vehicles would be expected to meet t he
alternate standards set specifically for the identified vehicle type, using a s implified GEM
interface

, where the engine and driveline

- specific GEM inputs would be set as EPA defaults, as described in the proposal for emergency vehicles. Election of this option c ould include the flexibility to comply on average within a weight class across a manufacturer’s custom production in that year , and it could includ e the flexibility to bank credits for future years

. However, it would not provide for trading of credits with other manufacturers , nor would it provide for internal averaging between custom and non

- custom vehicles in any model year

.

Table 3 lists the t echnologies the agencies are reviewing in the course of the feasibility analysis for custom chassis, their associated GEM inputs , and whether they would be available inputs under the simplified GEM certification approach. This table is not intended to indi cate our project ions of technologies to be applied for specific custom chassis. The vocation

- specific technology packages we are considering are presented below in Table s 4 , 5, and 6

.

Table 3 : GEM Inputs
Technology Associated GEM I nput Available in Simplified
GEM or Locked out as
Default Low Rolling Resistance Tires CRR level (kg/ton) Available Idle Reduction Technology (Stop

- Start or Neutral Idle) Yes or No Available

Part

- time Axle Disconnect Yes or No Available
Automatic Tire Inflation System (ATIS) Yes or No Available

Tire Pressure Monitoring System (TPMS) Yes or No Available

Weight Reduction Pounds reduced Available Coatings to manage solar loads Percent improvement Available Certified Engine Multi

- point fuel map Locked Out
Tire revs/mi Nearest cm Locked Out Driveline Integration or hybrid
driveline Powertrain test results Locked Out

Rear axle ratio 2 decimal places Locked Out Axle efficiency Multi

- point map from
separate test Locked Out

Transmission gear ratios 2 decimal places Locked Out Transmission gear efficiency 2 decimal places Locked Out Torque converter lockup Gear number Locked Out
Electrified accessories Percent improvement Locked Out Aerodynamic drag reduction Delta C D A Locked Out4

Technology Associated GEM I nput Available in Simplified
GEM or Locked out as
Default Improved PTO operation A

- B test results Locked Out

Low

- Leak Air Conditioning Components a N/A N/A

a Compliance with proposed standards to prevent leakage of HFC from air conditioning systems would be demonstrated using another method apart from GEM.

For any model year of the Phase 2 program , a manufacturer of vocational chassis that could otherwise qualify to be certified as custom vocational vehicles may elect to certify one or more families of vehicles to the primary standards using the full GEM

- based program th at includes engine fuel mapping

. Election of this option might include the flexibility to generate
and trade credits.

We are considering adopting provisions allowing manufacturer s of motor home, cement mixer, and emergency vehicle chassis to elect to cer tify one or more families of vehicles to an equivalent standard that would not require use of GEM, rather would rel y on installation of specific technologies. As currently envisioned, t his option would not include any averaging

, banking, or trading provisions. Such e quivalent technology

- based standards would not be
available for manufacturers of coach bus

, school bus, transit bus, and refuse truck chassis.

In Tables 4 , 5, and 6, the technologies described reflect the kinds of technology projected to form the basis for possible Phase 2 vehicle standards , and would apply in addition to technologies projected to meet the separate engine standard as well as HFC low

- leakage technologies. Where a tire CRR value is listed for the technology

- based package s, the combined value is obtained with the following formula: Steer tire CRR x 0.3 + Drive tire CRR x 0.7.

Table 4 : Possible MY 2021 Custom Vocational Vehicle Technology Packages

Vehicle Type Technology

- Based Packages Packages with Simplified GEM

Motor Home Combined CRR 6.7 kg/ton or less

, and

Neutral Idle if transmission has torque

converter

, and either TPMS or ATIS Combined t ire CRR 6.1 kg/ton

, 30 % neutral idle, 60 % TPMS

Coach Bus N/A HHD c ombined t ire CRR 6.3 kg/ton

, 3 0% neutral idle, 50 % TPMS

, 10% ATIS

Transit Bus N/A Combined t ire CRR 7. 7 kg/ton a

, 5 0% neutral idle, 10 % stop

- start, 40 % TPMS,
10% ATIS
School Bus N/A Combined t ire CRR 6. 9 kg/ton a

, 5 0% neutral idle, 5% stop

- start , 70 % TPMS

Refuse N/A Combined t ire CRR 7.7 kg/ton

, 50 % neutral idle, 10 % stop

- start, 40 % TPMS

, 10% ATIS5

Vehicle Type Technology

- Based Packages Packages with Simplified GEM

Emergency Combined t ire CRR 8.7 kg/ton or less Combined tire CRR 8. 4 kg/ton

Mixer Combined t ire CRR 7.6 kg/ton or less Combined tire CRR 7.6 kg/ton

a For light heavy

- duty transit and school buses, the agencies may allow a manufacturer to multiply the measured CRR by 0.87, as is currently allowed for vocational vehicles fitted with LT tires. The baseline data indicate that these vehicles have average CRR that is about 13% h igher than the average CRR of class 6

- 8 buses. This would be allowable for all years of the Phase 2 program.

Table 5 : Possible MY 2024 Custom Vocational Vehicle Technology Packages

Vehicle Type Technology

- Based Packages Packages with Simplified GEM

Motor Home Combined CRR 6.7 kg/ton or less

, and

Neutral Idle if transmission has torque

converter

, and either TPMS or ATIS Combined t ire CRR 6.1 kg/ton , 4 0% neutral idle, 70% TPMS

Coach Bus N/A Combined t ire CRR 6.1 kg/ton

, 4 0% neutral idle, 70% TPMS

, 5% ATIS , 5% part time 6x2 a
Transit Bus N/A Combined t ire CRR 7.7 kg/ton

, 6 0% neutral idle, 3 0% stop

- start, 45 % TPMS, 10% ATIS
School Bus N/A Combined t ire CRR 6. 6 kg/ton

, 6 0%
neutral i dle, 5% stop

- start, 90% TPMS,
5% ATIS
Refuse N/A Combined t ire CRR 7.7 kg/ton

, 6 0% neutral idle, 3 0% stop

- start, 45 %
TPMS , 10% ATIS Emergency Combined t ire CRR 8.7 kg/ton or less Combined tire CRR 8. 0 kg/ton

Mixer Combined t ire CRR 7.6 kg/ton or less Combined tire CRR 7.4 kg/ton

a Class 7 and below c oach bus es that do not have tandem rear axle would be instructed to enter an adjustment factor
in lieu of part time 6x2 technology.6 Table 6 : Possible MY 2027 Custom Vocational Vehicle Technology Packages

Vehicle Type Techno logy

- Based Packages Packages with Simplified GEM

Motor Home Combined CRR 6.0 kg/ton or less

, and

Neutral Idle if transmission has torque

converter

, and either TPMS or ATIS Combined t ire CRR 5.8 kg/ton , 70% neutral idle, 9 0% TPMS

Coach Bus N/A C ombined t ire CRR 5.8 kg/ton

, 7 0% neutral idle, 7 5 % TPMS

, 25% ATIS, 30 % part time 6x2 a
Transit Bus N/A Combined t ire CRR 6.8 kg/ton

, 5 0% neutral idle, 5 0% stop

- start, 40% TPMS,
30% ATIS
School Bus N/A Combined t ire CRR 6.2 kg/ton

, 7 0% neutral idle, 15 % stop

- start

, 8 0% TPMS,
20% ATIS
Refuse N/A Combined t ire CRR 6.8 kg/ton

, 5 0% neutral idle, 5 0% stop

- start, 4 0% TPMS

, 30% ATIS Emergency Combined t ire CRR 8.4 kg/ton or less Combined t ire CRR 7.6 kg/ton

Mixer Combined t ire CRR 7.1 kg/ton or less Combined t ire CRR 7.1 kg/ton

a Class 7 and below coach buses that do not have tandem rear axle would be instructed to enter an adjustment factor in lieu of part time 6x2 technology.

Another simplification being considered is to assign each type of custom chassis certified with simplified GEM to a single weight class that represents the majority of vehicles of that type. This would mean that all emergency vehicles, cement mixers, refuse trucks, transit buses, and coach buses would be certified with default GEM parameters as sociated with heavy heavy

- duty class 8 vehicles, including axle, engine, transmission, tare weight and payload defaults. This
would also mean that all school bus and motor home chassis would be certified with default GEM parameters associated with medium h eavy

- duty class 6

- 7 vehicles, including axle, engine, transmission, tare weight and payload defaults. Tables 7 and 8 present the default parameters that the agencies are planning to program in GEM for these vehicles. The agencies believe that the advantage s of this simplification would likely outweigh the disadvantages. Specifically, the differences in characterization of technology performance between weight classes is very small, on the order of tenths of a percent. Further, this would obviate the need fo r a manufacturer to certify multiple vehicle families , where one may have very small sales volumes.7 Table 7 : Custom Medium Heavy

- Duty Vocational Vehicle Predefined Modeling Parameters
Vehicle Type RV: MHD Regional School Bus: MHD Urban Engine 7L

- 270 hp diesel 7L

- 270 hp diesel
Transmission : Forward
Gears 6

- speed automatic : 3.102, 1.8107, 1.4063, 1, 0.7117, .61 5

- speed automatic : 3.102, 1.8107, 1.4063, 1, 0.7117

Total Weight (kg) 11,408 11,408 Payload (tons) 5.6 5.6
Number of Axles /Ratio 2 / 4.33:1 2 / 4.88:1
Tire Revs/Mile 517 517 Electrical Accessory Power (W) 300 300

Mechanical Accessory Power (W) 1,000 1,000

C D A (m 2 ) 5.4 5.4
Tire CRR = 0.7*Drive Crr +
0.3*Steer Crr = 0.7*Drive Crr +
0.3*Steer Crr Drive Cycles & Weightings :

CARB HHDDT .2 .92 GEM 55 mph cruise with

road grade .24 .07

GEM 65 mph cruise with

road grade .56 .01

Idle Cycle .22 .33

Table 8 : Custom Heavy Heavy

- Duty Vocational Vehicle Predefined Modeling Parameters

Vehicle Type Coach Bus: HHD Regional Transit, Refuse, Mixer, Emergency: HHD Urban Engine 11L

- 345 hp diesel 11L

- 345 hp diesel
Transmission: Forward
Gears 6

- speed automatic:
4.6957

, 2.213

, 1. 5291 , 1,
0.7 643, .6716 5

- speed automatic: 4.6957

, 2.213, 1.5291, 1, 0.7643

Total Weight (kg) 19,051 19,051 Payload (tons) 7.5 7.5
Number of Axles/Ratio 3 / 4.33:1 3 / 5.29:1
Tire Revs/Mile 496 496 Electrical Accessory Power (W) 300 300

Mechanical Accessory Power (W) 1,000 1,000

C D A (m 2 ) 6.86 6.86
Tire CRR = 0.7*Drive Crr +
0.3*Steer Crr = 0.7*Drive Crr +
0.3*Steer Crr8

Vehicle Type Coach Bus: HHD Regional Transit, Refuse, Mixer, Emergency: HHD Urban Drive Cycles & Weightings:

CARB HHDDT .2 .92 GEM 55 mph cruise with

road grade .24 .07

GEM 65 mph cruise with

road grade .56 .01

Idle Cycle .22 .33

Cost Estimates

Considering the above technology packages and the individual technology costs presented in the proposed rulemaking, the agencies estimate the incremental per

- vehicle costs for
custom vocational chassis would be less than the average per

- vehicle costs for the broader
vocational vehicle program.