SAE J661 APR2026 Brake Lining Quality Test Procedure

A stabilized SAE Recommended Practice for laboratory testing and reporting of brake lining friction and wear characteristics.

SAE J661 APR2026 establishes a uniform laboratory procedure for measuring and reporting the friction and wear characteristics of brake linings. The document defines test equipment requirements, drum temperature and speed controls, specimen and drum surface preparation, conditioning procedures, baseline, fade, recovery, and wear test runs, measurement requirements, friction coefficient evaluation, data presentation, and recertification tolerances. This stabilized edition was issued in April 2026 and supersedes SAE J661 OCT2021.

Application Scope: Intended for brake lining manufacturers performing in-plant quality control and purchasers assessing the quality of incoming brake lining shipments.