Changing rear pinion seal, is it hard and need torque specs?

**wolfie_ds** · 12-09-2006, 08:57 AM

I was up on stands for an oil change and noticed that I had a rear tranny seal leak and a rear pinion seal leak. The tranny seal is not really a problem to change but I have no idea on the rear yoke seal and the torque on the nut. Is there more to the process than just pulling the yoke off and changing the seal and replacing the yoke? Are there internal rearend parts that will be affected by this?

**Fran D** · 12-09-2006, 11:53 AM

Hmmmm...this is a little tricky, because the important specification is the preload torque on the pinion bearings, which can only be (accurately) measured while the pinion is not also turning the ring gear. Unless it's gushing oil, you may want to just leave this for now and attack it when you go through a rebuild (which, if it's the stock 10-bolt and you're hammering on it every once in a while, you'll need). Pulling the axles and the carrier seems like a lot of work unless it's an emergency.

**9t8z28** · 01-05-2007, 10:48 AM

Your gonna need a inch/pounds torque wrench under 30.

**Wesman** · 01-07-2007, 07:17 PM

Originally Posted by Fran D

Hmmmm...this is a little tricky, because the important specification is the preload torque on the pinion bearings, which can only be (accurately) measured while the pinion is not also turning the ring gear. Unless it's gushing oil, you may want to just leave this for now and attack it when you go through a rebuild (which, if it's the stock 10-bolt and you're hammering on it every once in a while, you'll need). Pulling the axles and the carrier seems like a lot of work unless it's an emergency.

According to the Chilton Shop manual, you shouldn't have to pull the axles or carrier to change the pinion seal. You need to remove the driveshaft, unscrew the nut, use a puller to remove the yoke, and then change the seal and reassemble. No adjusting if the bearings should need to be done to change the seal.

**Fran D** · 01-08-2007, 04:14 AM

Originally Posted by Wesman

According to the Chilton Shop manual, you shouldn't have to pull the axles or carrier to change the pinion seal. You need to remove the driveshaft, unscrew the nut, use a puller to remove the yoke, and then change the seal and reassemble. No adjusting if the bearings should need to be done to change the seal.

Yeah, in retrospect, there's probably a way to get it done. The GM Service Manual states to mark the yoke, pinion and nut so that it can be reassembled to achieve the appropriate preload. One just needs to take extraordinary care to get those three pieces lined up correctly after taking it apart. It could be done.