Heavy-duty vocational vehicles and tractors.
Heavy-duty vocational vehicles and tractors. This section describes the method for determining the fuel consumption performance rates for vehicle families of heavy-duty vocational vehicles and tractors. The NHTSA heavy-duty vocational vehicle and tractor fuel consumption performance rates correspond to the same requirements for EPA as specified in 40 CFR 1037, subpart F.
(1) Select vehicles and vehicle family configurations to test as specified in 40 CFR 1037.230 for vehicles that make up each of the manufacturer's regulatory subcategories of vocational vehicles and tractors. For the Phase 2 program, select powertrain, axle and transmission families in accordance with 40 CFR 1037.231 and 1037.232.
(2) Follow the EPA testing requirements in 40 CFR 1037.230 and 1037.501 to derive inputs for the Greenhouse gas Emissions Model (GEM).
(3) Enter inputs into GEM, in accordance with 40 CFR 1037.520, to derive the emissions and fuel consumption performance results for all vehicles (conventional, alternative fueled and advanced technology vehicles).
(4) For Phase 1 and 2, all of the following GEM inputs apply for vocational vehicles and other tractor regulatory subcategories, as follows:
(i) Model year and regulatory subcategory (see § 535.3 and 40 CFR 1037.230).
(ii) Coefficient of aerodynamic drag or drag area, as described in 40 CFR 1037.520(b) (tractors only for Phase 1).
(iii) Steer and drive tire rolling resistance, as described in 40 CFR 1037.520(c).
(iv) Vehicle speed limit, as described in 40 CFR 1037.520(d) (tractors only).
(v) Vehicle weight reduction, as described in 40 CFR 1037.520(e) (tractors only for Phase 1).
(vi) Automatic engine shutdown systems, as described in 40 CFR 1037.660 (only for Phase 1 Class 8 sleeper cabs). For Phase 1, enter a GEM input value of 5.0 g/ton-mile, or an adjusted value as specified in 40 CFR 1037.660.
(5) For Phase 2 vehicles, the GEM inputs described in paragraphs (b)(4)(i) through (v) of this section continue to apply. Note that the provisions related to vehicle speed limiters and automatic engine shutdown systems are available for vocational vehicles in Phase 2. The additional GEM inputs that apply for vocational vehicles and other tractor regulatory subcategories for demonstrating compliance with Phase 2 standards are as follows:
(i) Engine characteristics. Enter information from the engine manufacturer to describe the installed engine and its operating parameters as described in 40 CFR 1036.510 and 1037.520(f).
(ii) Vehicle information. Enter information in accordance with 40 CFR 1037.520(g) for the vehicle and its operating parameters including:
(A) Transmission make, model and type;
(B) Drive axle configuration;
(C) Drive axle ratio, ka;
(D) GEM inputs associated with powertrain testing include powertrain family, transmission calibration identifier, test data from 40 CFR 1037.550, and the powertrain test configuration (dynamometer connected to transmission output or wheel hub).
(iii) Idle-reduction technologies. Identify whether the manufacturer's vehicle has qualifying idle-reduction technologies, subject to the qualifying criteria in 40 and 1037.660 and enter values for stop start and neutral idle technologies as specified in 40 CFR 1037.520(h).
(iv) Axle and transmission efficiency. Manufacturers may use axle efficiency maps as described in 40 CFR 1037.560 and transmission efficiency maps as described in 40 CFR 1037.565 to replace the default values in GEM.
(v) Additional reduction technologies. Enter input values in GEM as follows to characterize the percentage CO2 emission reduction corresponding to certain technologies and vehicle configurations, or enter 0 as specified in 40 CFR 1037.520(j):
(A) Intelligent controls
(B) Accessory load
(C) Tire-pressure systems
(D) Extended-idle reduction
(E) Additional GEM inputs may apply as follows:
(1) Select vehicles and vehicle family configurations to test as specified in 40 CFR 1037.230 for vehicles that make up each of the manufacturer's regulatory subcategories of vocational vehicles and tractors. For the Phase 2 program, select powertrain, axle and transmission families in accordance with 40 CFR 1037.231 and 1037.232.
(2) Follow the EPA testing requirements in 40 CFR 1037.230 and 1037.501 to derive inputs for the Greenhouse gas Emissions Model (GEM).
(3) Enter inputs into GEM, in accordance with 40 CFR 1037.520, to derive the emissions and fuel consumption performance results for all vehicles (conventional, alternative fueled and advanced technology vehicles).
(4) For Phase 1 and 2, all of the following GEM inputs apply for vocational vehicles and other tractor regulatory subcategories, as follows:
(i) Model year and regulatory subcategory (see § 535.3 and 40 CFR 1037.230).
(ii) Coefficient of aerodynamic drag or drag area, as described in 40 CFR 1037.520(b) (tractors only for Phase 1).
(iii) Steer and drive tire rolling resistance, as described in 40 CFR 1037.520(c).
(iv) Vehicle speed limit, as described in 40 CFR 1037.520(d) (tractors only).
(v) Vehicle weight reduction, as described in 40 CFR 1037.520(e) (tractors only for Phase 1).
(vi) Automatic engine shutdown systems, as described in 40 CFR 1037.660 (only for Phase 1 Class 8 sleeper cabs). For Phase 1, enter a GEM input value of 5.0 g/ton-mile, or an adjusted value as specified in 40 CFR 1037.660.
(5) For Phase 2 vehicles, the GEM inputs described in paragraphs (b)(4)(i) through (v) of this section continue to apply. Note that the provisions related to vehicle speed limiters and automatic engine shutdown systems are available for vocational vehicles in Phase 2. The additional GEM inputs that apply for vocational vehicles and other tractor regulatory subcategories for demonstrating compliance with Phase 2 standards are as follows:
(i) Engine characteristics. Enter information from the engine manufacturer to describe the installed engine and its operating parameters as described in 40 CFR 1036.510 and 1037.520(f).
(ii) Vehicle information. Enter information in accordance with 40 CFR 1037.520(g) for the vehicle and its operating parameters including:
(A) Transmission make, model and type;
(B) Drive axle configuration;
(C) Drive axle ratio, ka;
(D) GEM inputs associated with powertrain testing include powertrain family, transmission calibration identifier, test data from 40 CFR 1037.550, and the powertrain test configuration (dynamometer connected to transmission output or wheel hub).
(iii) Idle-reduction technologies. Identify whether the manufacturer's vehicle has qualifying idle-reduction technologies, subject to the qualifying criteria in 40 and 1037.660 and enter values for stop start and neutral idle technologies as specified in 40 CFR 1037.520(h).
(iv) Axle and transmission efficiency. Manufacturers may use axle efficiency maps as described in 40 CFR 1037.560 and transmission efficiency maps as described in 40 CFR 1037.565 to replace the default values in GEM.
(v) Additional reduction technologies. Enter input values in GEM as follows to characterize the percentage CO2 emission reduction corresponding to certain technologies and vehicle configurations, or enter 0 as specified in 40 CFR 1037.520(j):
(A) Intelligent controls
(B) Accessory load
(C) Tire-pressure systems
(D) Extended-idle reduction
(E) Additional GEM inputs may apply as follows:
Source
49 CFR § 535.6
Scoping language
This part describes the measurement and calculation procedures manufacturers use to determine annual fuel consumption performance results. Manufacturers use the fuel consumption results determined in this part for calculating credit balances specified in 535.7 and then determine whether they comply with standards as specified in 535.10. Manufacturers must use EPA emissions test results for deriving NHTSA's fuel consumption performance rates. Consequently, manufacturers conducting testing for certification or annual demonstration testing and providing CO2 emissions data to EPA must also provide equivalent fuel consumption results to NHTSA for all values. NHTSA and EPA reserve the right to verify separately or in coordination the results of any testing and measurement established by manufacturers in complying with the provisions of this program and as specified in 40 CFR 1037.301 and 535.9. Any carry over data from the Phase 1 program may be carried into the Phase 2 only with approval from EPA and by using good engineering judgment considering differences in testing protocols between test procedures.