SAE J 1646

This document has been declared Stabilized and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability or technical requirements. New technology may exist.This SAE Recommended Practice defines the principal terms and equations pertaining to automotive automatic transmission clutch plate, band, or other wet-friction systems. The terms apply directly to friction-system testing as a typically conducted on inertia-stop test equipment. Some terms can be directly applied to the analysis of friction in the transmission or brake assembly and other friction-test equipment.The glossary presents terms used to describe the set-up, testing, and results of tests as shown in Figure 1, which were taken on a clutch SAE No. 2 machine.The glossary is intended to provide a collection of definitions in the hope of eliminating confusion in terminology and a common set of terms for improve the state-of-the-art of friction-system development and their application to passenger cars and trucks.This document focuses on the terminology of friction-system testing. Reference for this type of testing are shown in Section 2.

This product replaces:SAE J 1646 - Glossary of Terms~Lubricated Friction Systems