Tucked behind the axle shaft where it exits the differential casing, the shaft seal for the differential is a small lip seal that performs one essential job: preventing differential oil from escaping along the shaft while keeping road contaminants out of the gear oil. On most front-wheel-drive cars the differential is integrated into the gearbox, making the seal a transaxle output seal; on rear-wheel-drive and four-wheel-drive platforms it sits at the differential housing proper. When this seal fails โ typically because the lip hardens and cracks with age, or the running surface on the shaft develops a wear groove โ differential oil begins to seep out. The first sign is usually a small oil patch on the driveway beneath the axle or a visible wet stain on the differential casing near the driveshaft flange. Left unattended, the oil loss eventually drops gear oil to a level where it cannot adequately lubricate the crown wheel and pinion, leading to expensive differential damage. Corteco and Elring are established manufacturers of precision rubber shaft seals, supplying both OEM production lines and the aftermarket. Because seal bore diameter, shaft diameter, seal width, and lip geometry must all match the casing bore and shaft journal exactly, the OE number is the only reliable way to identify the correct seal โ even a fractional dimensional mismatch will cause the new seal to leak immediately.
Differential shaft seals are defined by bore diameter (the inside of the casing), shaft diameter, seal width, and lip design โ parameters that vary between differential housings, shaft diameters, and generations of the same platform. Each listing on this page shows TecDoc OE references linked to specific vehicles and axles. Use your vehicle's make, model, engine, and year to confirm. If replacing on a high-mileage vehicle, also check the shaft journal for a wear groove โ if the groove is deep, a repair sleeve may be needed alongside the new seal.
OEM seals are manufactured by specialist suppliers such as Corteco or Elring to the vehicle builder's elastomer compound and dimensional specification, ensuring the correct friction coefficient and chemical resistance to gear oil additives. Quality aftermarket seals from the same manufacturers carry identical OE references. Low-cost alternatives may use a different rubber compound that swells or hardens in contact with modern gear oil additives, causing premature failure โ sometimes within a few thousand miles of fitting.
Not always, but it is generally prudent to inspect both sides. On a front-wheel-drive transaxle, both output shaft seals are the same age and subject to similar conditions, so if one has failed the other is likely to follow soon. Replacing both during the same gearbox drain cycle adds minimal extra cost and avoids a repeat job within months. On rear-axle differentials with separate left and right seals, the same logic applies โ once the oil is drained and the shaft is out, the additional work is small.
The most obvious sign is a wet, oily patch or drip beneath the vehicle directly behind the wheel, on the inboard face of the drive axle or at the differential housing flange. On front-wheel-drive cars, gear oil mist may be thrown inside the wheel arch. In either case the smell of warm differential oil is distinctive. If the leak is significant enough to reduce gear oil level, the driver may notice increased differential whine under load or, in severe cases, resistance or vibration at the wheel caused by insufficient lubrication.
Showing 100 of 2,375 Differential shaft seal OE numbers. Enter the OE on the main OE search to jump to any reference.
