Interim Requirements to Determine 

Eligibility of SmartWay Tractors

 

U.S. Environmental Protection 

Agency Designated SmartWay 

tractors and trailers are a new 

generation of long-haul rigs 

equipped with cleaner, fuel-saving 

features. SmartWay tractors and 

trailers can achieve fuel savings 

of 10 to 20 percent (saving carriers between 1,700 and 3,300 

gallons of diesel fuel annually), 

lower greenhouse-gas emissions, 

and significantly reduce oxides of 

nitrogen, particulate matter, and 

other air pollutants. 

This document describes the 

interim requirements (both design 

and performance) for adding 

tractors to the existing list of 

SmartWay designated trucks.

Purpose of Interim Requirements

The U.S. Environmental Protection Agency (EPA) developed these interim requirements to determine eligibility for SmartWay designation of Class 8 sleeper-cab 

tractors.1

 These interim requirements are intended to permit truck manufacturers to add SmartWay-designated sleeper-cab tractor models to the current list of 

SmartWay-designated Class 8 tractors.2 These interim requirements replace all 

prior EPA guidance and direction to truck manufacturers and truck purchasers on 

how to determine eligibility for SmartWay-designated tractors. 

Interim Requirements

To be eligible for SmartWay designation, a tractor must be a Class 8 sleeper-cab 

tractor and meet the following design, performance and licensing requirements.

1. Design Requirement

All SmartWay designated tractors will have the folloiwng design features:

 a. New model (newly introduced into commerce), not a retrofit. 

 b. Sleeper cab intended for over-the-road line haul operation.

 c. Aerodynamic profile (sloping hood, curved features), no 

 “classic-style” tractors (long nose, flat hood, flat, squared-off grill) 

 will be considered eligible even if they meet other requirements.

 d. Equipped with the following components and features:

 (1) 2007 or newer EPA-compliant engine, as determined by 

 federal emissions certification testing. 

 (2) Roof fairing attached to the cab roof that extends the

 uppermost height of the integrated cab roof and fairing to approxi- 

 mately at or above the height of a typical (53’ L x 102” W x 13’6” H) dry 

 box van semi-trailer when such a trailer is attached to the tractor, to 

 help maintain smooth air flow across the top surface of the combined 

 tractor and trailer (“integrated roof fairing”).3 

1 This method is an interim method, in effect until the US Environmental Protection Agency (EPA) finalizes a more comprehensive greenhouse 

gas emissions test protocol for medium duty and heavy duty commercial on highway vehicles. When the more comprehensive test protocol 

is finalized, EPA plans to establish new performance-based eligibility criteria for SmartWay certification of Class 8 sleeper-cab tractor-trailers 

using the new more comprehensive test method. EPA will consider using the finalized test protocol to expand SmartWay certification to other 

truck configurations and classes.

2 EPA initially limited each truck manufacturer to two (2) SmartWay-certified Class 8 sleeper-cab tractor models in each truck make (brand). 

The initial SmartWay-certified models were selected on the basis of their fuel efficiency. To be eligible, a manufacturer had to confirm to 

EPA that the model or models were the most fuel-efficient model or models offered in that truck make. A manufacturer evaluated the fuel 

efficiency of its truck models using industry-accepted test methods, including the Joint TMC/SAE J1321 Fuel Consumption Test Procedure 

Type II RP J1321; the TMC RP 1109 Type IV Fuel Economy Test Procedure; computational fluid dynamics (CFD) modeling; and wind tunnel 

testing. Additionally, the models had to be equipped with the following features: 2007 or newer EPA-compliant engine, as determined by 

federal emissions certification testing; integrated roof fairing; cab side extender fairings; side fuel tank fairings; aerodynamic mirrors; 

aerodynamic bumper; low rolling resistance EPA-verified tires; aluminum wheels encouraged, but not required; and an idle reduction system 

capable of providing eight (8) or more continuous hours of idle-free operation for the main truck engine.

3 Actual trailer height from the ground to the roof of the trailer depends upon a combination of factors including trailer dimensions, fifth 

wheel setting, wheel and tire size, etc.

Summary of SmartWay 

Tractor & Trailer 

Program

SmartWay Transport | EPA-420-F-09-045 | www.epa.gov/smartway | 734-214-4767 | SmartWay-tech@epa.gov

May 2011
 (3) Fairings that extend back from the sides of the

 cab to help maintain smooth air flow across the 

 tractor-trailer gap (“cab side extender fairings”).

 (4) Fairings that cover the side fuel tanks to help

 maintain smooth air flow over the fuel tanks

 (“side tank fairings”).

 (5) Mirrors with a curved housing to help maintain

 smooth air flow over the mirrors (“aerodynamic 

 mirrors”).

 (6) A bumper that curves inward at the bottom and

 sides, to help maintain smooth air flow under and

 around the tractor (“aerodynamic bumper”).

 (7) Low rolling resistance EPA-verified low rolling 

 resistance tires.4

 

 (8) Idle reduction system capable of providing eight 

 (8) or more continuous hours of idle-free 

 operation for the main truck engine.5 

 e. Aluminum wheels and other light-weight 

 components are encouraged, but not required. 

2. Performance Requirement

The tractor must demonstrate that it meets or 

exceeds the fuel efficiency performance of at least one current 

SmartWay-designated sleeper-cab tractor model, of any make 

from any manufacturer. To demonstrate that a tractor meets 

this fuel efficiency requirement, it must be tested using the Joint 

TMC/SAE J1321 Fuel Consumption Test Procedure Type II RP 

J1321, as modified by EPA. Testing must the following specific 

requirements:

a. The SAE J1321 test must be conducted according to EPA’s 

interim J1321 Test Method.

b. The make and/or manufacturer need not match that of the 

candidate tractor. However, EPA must approve of the reference tractor / candidate tractor configurations.

c. The manufacturer must have its test plan approved by EPA 

prior to testing. 

d. The manufacturer must share raw test data, as well as other 

test information (test conditions, test method, test facility, 

comparison tractor, etc.) with EPA as part of its submission 

for SmartWay certification.

e. EPA reserves the right to disregard tests that it judges to 

be invalid because the conduct of the test, or the test facilities, conditions, test equipment, or vehicles fail to meet the 

provisions of the test method or EPA’s supplemental test 

guidelines, or because EPA determines that the reported 

results are incompatible with good engineering judgment. 

f. The manufacturers will submit a test report to EPA that includes signatures from the test facility and manufacturer 

certifying that the test was conducted in accordance with 

4 A list of SmartWay-verified low rolling resistance tire models is available at: 

http://www.epa.gov/smartway/transport/what-smartway/verified-technologies.htm#tires 

5 The truck purchaser can choose the manufacturer-offered idle reduction system or an EPA-approved 

alternative. The purchaser must demonstrate to EPA that the alternative option provides eight (8) or more 

continuous hours of idle-free operation.

the SAE J1321 as modified by the most recent EPA requirement.

3. Licensing Requirement

Once EPA determines that a sleeper-cab tractor model is eligible 

for SmartWay designation, the manufacturer must submit a 

request to EPA to license the model as a SmartWay-designated 

vehicle. If a truck owner wants to display an external SmartWay 

logo on a SmartWay-eligible sleeper-cab tractor, the truck owner 

must complete a separate logo request and equipment check 

list with EPA. 

Right of Exclusion

EPA reserves the right to withhold SmartWay designation if in 

its estimation the proposed truck model does not meet these 

design, performance, or licensing requirements. 

Testing Costs

The manufacturer bears all costs for testing. 

Contact EPA

• For general information about SmartWay and SmartWaydesignated tractors and trailers, visit the EPA SmartWay 

web site at www.epa.gov/smartway.

• For further information related to these interim eligibility 

requirements and the interim test method for SmartWay 

designation of sleeper-cab tractors, contact the SmartWay 

technical e-mail center at SmartWay-tech@epamail.epa.gov.

In general, to contact EPA, 

• send an e-mail to: SmartWay-tech@epa.gov

• telephone the SmartWay Transport Partnership Call Center 

at (734) 214-4767

• write to SmartWay Transport Partnership, US EPA, 2000 

Traverwood, Ann Arbor, MI 48105. 

SmartWay Transport | EPA-420-F-09-045 | www.epa.gov/smartway | 734-214-4767 | SmartWay-tech@epa.gov