Annotation of standard text SAE J1379 :
This recommended practice applies to the laboratory measurement of the rolling resistance of pneumatic tires designed primarily for use on trucks and buses in normal highway service, as defined by the Tire and Rim Association, Inc. (TRA); it does not include light truck tires (designated LT). The procedure applies only to straight, free-rolling tires under steady-state operation and includes the following three basic methods:
SUBFILE: Automotive
TYPE OF DOCUMENT: Ground Vehicle Standard
Stabilized: Nov 2020 