Dorman Engine Rear Main Seal Cover
Dorman Engine Rear Main Seal Covers: Engineered to Stop Leaks for Good
A leaking rear main seal is one of the more frustrating engine oil problems a vehicle owner can face. The rear main seal cover — sometimes called the rear main seal retainer or housing — is the structural component that holds the crankshaft's rear seal in place and keeps engine oil from escaping where the crankshaft exits the block. When this cover warps, cracks, or develops a compromised sealing surface, oil finds its way out. Dorman has developed a focused lineup of engine rear main seal covers designed to address this problem cleanly, completely, and with parts that are built to last.
What Sets Dorman Apart in This Category
Since 1918, Dorman has been the automotive aftermarket's pioneering problem solvers, releasing thousands of parts and components that people could once only buy from original equipment manufacturers — always innovating to lead the way in growing the aftermarket. That same philosophy carries directly into their rear main seal cover offerings.
Dorman's rear main seal cover kits match the factory design and include a new gasket, installation hardware, and an updated seal design for superior leak prevention. Rather than selling just a bare housing that forces the technician to source additional components, Dorman bundles everything needed for a complete repair in one box — a genuine time-saver in the shop.
The flagship kit in this lineup, part number 635-518, exemplifies Dorman's commitment to material upgrades. Crafted from high-quality aluminum, this cover ensures long-lasting performance and resistance to wear, and comes complete with the cover, seal, and gasket for a full installation. The aluminum construction provides excellent resistance to corrosion and heat, while the precision inside diameter ensures a tight seal around the crankshaft.
The 635-518 kit is specifically designed for Chevy and GMC vehicles equipped with 4.8L, 5.3L, 6.0L, and 6.2L engines — platforms known for their widespread use in trucks, SUVs, and full-size vans. Compatible vehicles include the Buick LaCrosse, Cadillac CTS, Chevrolet Camaro, GMC Canyon, Hummer H2, Pontiac G8, and Saab 9-7x, among others.
For applications requiring a straightforward retainer-style replacement rather than a full kit, Dorman also offers the 635-557 rear main seal retainer. This direct replacement matches the fit and function of the original equipment cover and is made of quality materials for a reliable fit and enduring service life.
The Dorman OE FIX Philosophy Applied to Sealing
When a Dorman product is marked OE FIX™, it is designed to offer a better repair solution than the OEM. Repair professionals and vehicle owners are often frustrated when trying to fix cars and trucks using original equipment, since original manufacturers don't always provide parts that minimize cost and installation time, or maximize future reliability and serviceability — and that's where Dorman steps in. The inclusion of updated seal designs and pre-assembled hardware in their rear main seal cover kits is a direct reflection of this mission.
Each kit matches the fit and function of the original equipment cover for a reliable repair, and has undergone extensive testing to ensure adherence to precise design standards. For DIYers and professional mechanics alike, that means fewer surprises on the lift and more confidence in the finished repair.
Whether you're addressing an active oil leak on a high-mileage GM truck or performing preventive maintenance on a rebuilt engine, Dorman's engine rear main seal covers offer a complete, well-engineered solution from a brand with over a century of aftermarket experience. Explore the full range of Dorman products to find everything you need to keep your engine sealed and running clean.
