This SAE Recommended Practice describes application of two closely related test procedures@ which together determine the linear range longitudinal and lateral stiffnesses of a statically loaded non-rotating tire. The procedures apply to any tire so long as the equipment is properly sized to correctly conduct the measurements for the intended test tire. The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTE: Herein@ road load models are models for predicting forces applied to the vehicle spindles during operation over irregular pavements. Within the context of this document@ forces applied to the pavement are not considered. Procedures Two closely related procedures are applied. In each procedure@ the contact center of a loaded tire on a locked spindle and its wheel center are displaced horizontally@ one with respect to the other@ so as to generate shear force versus shear deflection data. In the first procedure@ the displacement is purely longitudinal@ parallel to the X??-axis in the SAE Tire Axis System. In the second procedure@ the displacement is purely lateral@ parallel to the Y??-axis in the SAE Tire Axis System. These procedures are spelled out in the body of this document. Test Machines This document is test machine neutral. It may be applied using any type of test machine capable of fulfilling the requirements stated in this document. The test machine must be capable of accommodating the tire sizes to be tested.