This terminology aims to encompass all terms and definitions pertaining to the road performance of pneumatic tires designed for over-the-highway use, such as passenger car, light truck, truck and bus, and motorcycle tires. Not included are terms specific to the performance of agricultural, aircraft, industrial, and other off-highway tires. However, many terms contained in this document also apply to non-highway tires.
SAE J2047 was originally developed to gather together existing tire and pertinent wheel terms and their definitions developed by different standards organizations so as to provide a convenient single source for technical terms related to tire performance. Since the original development of SAE J2047, there have been numerous changes within the literature from which the definitions in the original version of this Recommended Practice were drawn. In particular 2007 changes in SAE J670 have rendered the 1998 version of this terminology obsolete due to a change in the sense of positive spindle torque within the Z-down Tire Coordinate System, which is intended to replace the Tire Axis System found in SAE J670e and its predecessors. It is, therefore, necessary to revise SAE J2047 so that it once again achieves its intended purpose of providing a one document reference to tire performance terminology.