Description

The Cummins Rear Seal Sleeve 3906081 is a precision-engineered diesel engine component designed to restore a smooth and consistent sealing surface for the rear crankshaft seal , ensuring long-term oil leak prevention in Cummins diesel engines. This sleeve is a direct replacement for Cummins OEM part number 3903476 , making it ideal for rear main seal service, lower-engine repairs, and complete engine rebuilds. Manufactured from high-quality, wear-resistant steel , this rear seal sleeve is built to withstand continuous seal contact, high rotational speeds, oil exposure, and harsh operating conditions typical of heavy-duty diesel engines. The precision-finished surface provides an optimal interface for the rear crankshaft seal, helping extend seal life and prevent leaks caused by worn or grooved crankshaft sealing areas. Designed for accurate fitment and dependable performance , the Cummins 3906081 rear seal sleeve helps maintain proper oil retention, protect internal engine components, and reduce downtime associated with repeat seal failures. Installing a new seal sleeve during rear crankshaft seal replacement is strongly recommended to ensure OEM-level sealing reliability. This rear seal sleeve is commonly used as part of a lower gasket set or as a standalone replacement in Cummins diesel engine rebuild and rear-end repair applications , including on-highway trucks, industrial engines, and heavy-duty equipment.