The information report provides background information related to the development of the SAE Recommended Practice that produces relative fuel economy data.
SAE J1420-1983 history
1997SAE J1420-1997 Supportive Information Report for the Fuel Economy Measurement Test (Engineering Type) for Trucks and Buses
1988SAE J1420-1988 Supportive Information Report for the Fuel Economy Measurement Test (Engineering Type) for Trucks and Buses
1983SAE J1420-1983 Supportive Information Report for the Fuel Economy Measurement Test (Engineering Type) for Trucks and Buses