This SAE Recommended Practice establishes uniform engineering nomenclature for wheels@ hubs@ rims@ and their components used in truck@ bus@ and trailer applications. This nomenclature and accompanying drawings are intended to define functional truck wheel@ hub@ and rim designs. For nomenclature specific to ??passenger-type?? disc wheels@ refer to SAE J1982. The International Standard (ISO) nomenclature is shown in parentheses when different than SAE J393.