Had the TB up on the lift at work the other day changing out the thermostat again and also decided to do a brake flush as well. When I got to the back I noticed that the seal on the front of the rear diff (the part where the driveshaft connects to the rear diff) was leaking and slinging fluid everywhere. Luckily it's not puking fluid more seeping, but I was wondering if anyone's done this repair and do I need just the seal or should I replace anything else while I'm in there? The TB is an 06 4.2L with a GU6 RPO code. Thanks in advance.
Rear Diff Leaking
- Thread starter LouisTB
- Start date
It's Good to hear from you, Brother...
This Video is Generic... But covers the Rear Pinion Seal R&R on GMC Rear Differentials with enough Professional Detail and Good Tips to be valid for your SUV:
This Video is Generic... But covers the Rear Pinion Seal R&R on GMC Rear Differentials with enough Professional Detail and Good Tips to be valid for your SUV:
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Mooseman
Moderator
One thing he doesn't mention in the video is to remove the fill plug FIRST. If it's stuck, at least you're not out of diff lube and can still use the truck with the lube that's still in it until you can get the plug out. I'm also not in favour of using an impact to put the nut back on. Use two of the U-joint bolts and use a long screwdriver or pry bar in them to hold the pinion while tightening using a socket and ratchet or breaker bar by hand.
m.mcmillen
Member
Also, check the yoke and be sure that the seal hasn't worn a groove in the yoke. If it has, you need to get a new yoke.
- Jul 22, 2015
- 2,724
Imma have to do my own on the Voy; noticed the other day when I replaced the brake line that the bottom of the diff was wet (as was my garage floor underneath it). Then I traced it up to what I knew would be the pinion seal. That'll be fun. But the Envoy's gonna hopefully be parked for the next few months, so I'll worry about it later.
