

                 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                NATIONAL VEHICLE AND FUEL EMISSIONS LABORATORY
                             2000 TRAVERWOOD DRIVE
                           ANN ARBOR, MI  48105-2498


									     OFFICE OF
									AIR AND RADIATION

August 8, 2016

MEMORANDUM

SUBJECT: 	Tire Rolling Resistance Data from Smithers Rapra Laboratory in the Proposed Heavy-Duty Phase 2 Greenhouse Gas Rulemaking

FROM: 	Prashanth Gururaja, Assessment and Standards Division, Office of Transportation and Air Quality

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

Tire rolling resistance tests were conducted at Smithers Rapra laboratory to understand the speed dependence of tire rolling resistance. Tests were conducted using a modified SAE J2452 stepwise coastdown procedure and the SAE J1269 and ISO 28580 constant-speed procedures at multiple speeds. Attached are 12 data files containing the test conditions and results for the three SmartWay-verified tire models used in the on-road aerodynamic evaluation. The analysis using these results is described in Chapter 3.2 of the Regulatory Impact Analysis.
