Pinion Seal Mopar 8.75in

The Pinion Seal Mopar 8.75in from RATECH is an essential replacement component for Mopar differentials, specifically engineered for 8.75-inch and 9.25-inch rear axle assemblies. As a mechanic or dedicated enthusiast tackling differential maintenance or rebuilds, you'll recognize this seal as a critical barrier protecting your gear oil from leaking past the pinion yoke. When factory seals degrade—whether from age, heat cycling, or contamination—differential fluid escapes, leading to accelerated wear of gears, bearings, and other internals. This RATECH pinion seal restores that leak-free barrier and is a must-have for any serious axle service or restoration project.

This seal features a dual-material construction combining rubber and steel components, a proven design that withstands the extreme pressures and temperatures inherent in differential operation. The rubber lip creates the dynamic seal against the pinion yoke, while the steel backing ring provides structural integrity and retention in the axle housing bore. RATECH's manufacturing standard ensures dimensional precision—the compact 3.8 x 0.75 x 4.1-inch form factor guarantees correct fit without modification. The minimal weight of 0.14 lbs reflects its purpose-built efficiency, with zero unnecessary material compromising either reliability or installation ease.

Anyone rebuilding a Mopar 8.75-inch or 9.25-inch differential—whether in a classic Dodge, Plymouth, or Chrysler muscle car or a later Jeep application—should stock this seal. Installation is straightforward during axle removal: drive out the old seal, clean the bore thoroughly, and press in the new unit using a seal driver or appropriately sized socket. This seal is sold individually, so verify your axle configuration before ordering. Pairing this with fresh differential fluid and a complete rebuild kit ensures your rear axle will run cool, quiet, and leak-free for years of reliable performance.