Since 1921, Cloyes has been the trusted leader in automotive timing systems. As a critical component of the engine?s timing system, the idler sprockets work in unison with the timing chain, crankshaft sprockets, camshaft sprockets, tensioners, and guides, to ensure precise timing. Cloyes engine timing idler sprockets are precision-tooled with exact tooth geometry and a perfectly matched bore with bushing and/or idler post if needed, off-set and timing index for superior fit, reliability, and long-term performance. To ensure total timing system integrity, Cloyes recommends replacing the chain along with the tensioners, guides, and sprockets during service. Trusted by professionals for over a century & backed by an industry-leading warranty and technical support.