GM Differential Cover Gasket 8.875 12-Bolt Trk

The GM Differential Cover Gasket 8.875 12-Bolt Trk by FEL-PRO (RDS 13391) is a critical sealing component engineered for GM trucks equipped with 8.875-inch 12-bolt differentials. Whether you're performing routine differential maintenance, replacing a leaking cover gasket, or rebuilding a rear axle assembly, this gasket prevents gear oil from seeping past the differential cover and contaminating your driveline. Any serious truck owner or mechanic knows that differential leaks lead to rapid wear of gears and bearings—making a quality replacement gasket essential for long-term reliability.

FEL-PRO's differential cover gasket is manufactured to OEM specifications, ensuring a precise fit between the cover and the differential housing. The gasket material is formulated to withstand the high pressures and temperatures generated during heavy towing, offroad use, and sustained highway driving. Its 0.25-inch thickness and engineered compound resist gear oil degradation and maintain a permanent seal without hardening or shrinking over time. The compact dimensions (12.25 x 12.75 inches) correspond exactly to the 12-bolt cover pattern, guaranteeing alignment with all mounting points and eliminating the risk of misalignment-induced leaks.

This gasket is ideal for owners of full-size GM trucks with 8.875-inch differentials, including C/K-series pickups and SUVs spanning multiple generations. Installation is straightforward—remove the differential cover, clean the mounting surface thoroughly, and seat the new gasket before torquing the cover bolts to specification. Whether you're addressing an existing leak or performing preventive maintenance during a differential service, this FEL-PRO gasket delivers OEM-grade performance at an accessible price point. Always pair with fresh differential fluid and proper torque procedure for a lasting, leak-free seal.