EI08267 - Rear Axle Pinion Seal Leak (Engineering Information)

Some customers may comment on a leak from the rear of the vehicle. Diagnose the vehicle to determine the source of the leak.

Complete the following steps ONLY if the source of the leak is the rear axle pinion seal. If the source of the leak is other than the rear axle pinion seal, disregard this bulletin, diagnose and repair according to information published in SI.

Note the following information on the repair order:

1. Verify that the VIN and mileage are accurately recorded on the repair order.
2. Inspect for leakage at other locations (output seals, vent, plugs) that may have been identified as a pinion seal leak. Note any other visible leaks.
3. If possible, take detailed digital pictures of the leakage at the pinion seal as-is from the customer (no cleaning, etc.). E-mail all digital photos to: richard.burrell@gm.com (make sure VIN, R.O., Dealer Name, Location and Dealer Code information is contained in e-mail).
4. Inspect for incorrectly assembled seals (cocked at an angle, not fully pressed in, etc.).
5. Inspect for damage to the slinger (unseated, dings, broken welds, etc.).
6. How was the leak was found? Is this a concern that the customer brought the vehicle in for, or did the technician discover the leak during inspection?
7. Drain the fluid and measure the quantity.

Important:  The rear axle assembly should not be replaced unless directed by engineering.

8. Contact the appropriate engineer. The engineer may request the pinion seal back for analysis. All parts will be requested back using the Warranty Parts Center (WPC) process.

If engineering is unable to take the call, leave the following information. If a returned called is not received within one hour, diagnose and repair the vehicle according to information found in SI.

-	Technician Name

-	Dealership Name, Location, Dealer Code and Phone Number

-	VIN and Repair Order Number

For vehicles repaired under warranty, use: