I haven't seen a write up and mine needed it, so I thought I'd do one. Its a fairly common problem as the miles rack up. Its pretty easy and straight forward, but for the person new to wrenching a little help is always good.
Here is how i knew my rear end was starting to leak. It looks like it was leaking for a while because the truck sat for 8 months before I fixed it.
Things You'll need:
3 quarts 75-140 gear oil
Axle Seals. I recommend 2, and doing both sides at the same time. I got mine at Randy's ring and pinion for about $25 for the pair. Randy's Ring & Pinion. The Differential Experts. Auto Parts & Services.
A few cans of brake clean
1 tube of RTV. I am a big fan of the sealant that GM uses, and its the only stuff I buy. Just go to your local gm dealer and ask for a tube of GMS. If you don't want to do that, just get a tube of black rtv.
Can of PB Blaster or WD40
Tools:
Floor Jack
Jack stands
Drain Pan
3/8" Ratchet or air ratchet
1/2" socket
10mm socket
dead blow hammer
8mm socket
snap ring pliers
Large magnet or pliers
Pry Bar
Medium screw driver
Snap ring pliers(tru trac only)
I'm only showing pictures of 1 side as they are identical.
Begin by blocking the front tires and lifting the rear end. Secure the vehicle on a pair of jack stands and remove the rear tires. I left the vehicle in neutral to rotate the drive line to be able to get to the center pin on the carrier. If you don't have air tools be sure to crack loose the lug nuts prior to lifting the rig.
At this point I removed the differential cover to allow the housing time to drain. The bolts are 1/2". Remove all of them but the top 1 or 2, which you just loosen. This will prevent the fluid from dumping out when the differential cover falls off. Once all the bolts are out and loosened, use the screw driver to pry the cover back. It will be a bit sticky from the last round of sealant that was used.
Which will leave you with this.
While the housing is draining go ahead and remove the calipers. There are 2 bolts holding them, and it takes a 10mm socket to get them off. Once removed just set them on the rear leaves, out of the way. Do Not leave them hanging.
Next you'll remove the rotors.
Spray a bit of PB blaster or WD40 onto the hub of the rear axle to loosen it up, then hit the back side of the rotor with the dead blow, or hammer and wood until it comes loose. At that point it will slide right off.
Now you are ready to move back to the differential to remove the center pin and c-clips, or if you have a tru trac, the assembly in the center of the carrier.
On the stock carrier use the 8mm socket to remove the bolt and then remove the center pin.
On a tru trac remove the snap ring. There are 2 pieces that will come out with snap ring. This will allow you access to the c-clips.
At this point, push the axle shaft into the housing to allow you to remove the c-clip. With either a large magnet or a pair of needle nose plier, remove the c-clips and set them aside.
Now, you can support the axle shaft and pull it straight out. Now would be a good time to inspect your shaft for any pitting or marks. If you have any, a fine piece of sand paper or emry pad will clean it up.
After my axle was removed further evidence of the leak was found
At this point I decided to clean out the housing of the old fluids and such prior to reassembling things.
I used a large pry bar to pop the seal out, here is the old seal and bar I used
At this point you'll want to clean up the area where the seal was at prior to installing your new seal.
Then using a dead blow install the new seal ensuring you get it flush
Next, slide the axle shaft back in and just reverse the process.
I used a small screw driver and hammer to tap the c-clips back into place.
At this point take your differential cover and using a gasket scraper clean all the old RTV off of it. Once all the large stuff was gone I used a wire wheel to clean up the rest of it.
Do the same to the housing
Apply a small bead of RTV to the cover and re-install the bolts.
Lastly its time to fill your diff. The owners manual calls for 2.7 liters of fluid or about 2.5 quarts.
the fill hole takes a 3/8" square drive to remove it.
When you get fluid just starting to dribble out you are done, re-install the plug, put your tires back on and set the truck down.
If you have any tools or helpers left under the truck, make sure they are out of the way... HAHA
Here is how i knew my rear end was starting to leak. It looks like it was leaking for a while because the truck sat for 8 months before I fixed it.
Things You'll need:
3 quarts 75-140 gear oil
Axle Seals. I recommend 2, and doing both sides at the same time. I got mine at Randy's ring and pinion for about $25 for the pair. Randy's Ring & Pinion. The Differential Experts. Auto Parts & Services.
A few cans of brake clean
1 tube of RTV. I am a big fan of the sealant that GM uses, and its the only stuff I buy. Just go to your local gm dealer and ask for a tube of GMS. If you don't want to do that, just get a tube of black rtv.
Can of PB Blaster or WD40
Tools:
Floor Jack
Jack stands
Drain Pan
3/8" Ratchet or air ratchet
1/2" socket
10mm socket
dead blow hammer
8mm socket
snap ring pliers
Large magnet or pliers
Pry Bar
Medium screw driver
Snap ring pliers(tru trac only)
I'm only showing pictures of 1 side as they are identical.
Begin by blocking the front tires and lifting the rear end. Secure the vehicle on a pair of jack stands and remove the rear tires. I left the vehicle in neutral to rotate the drive line to be able to get to the center pin on the carrier. If you don't have air tools be sure to crack loose the lug nuts prior to lifting the rig.
At this point I removed the differential cover to allow the housing time to drain. The bolts are 1/2". Remove all of them but the top 1 or 2, which you just loosen. This will prevent the fluid from dumping out when the differential cover falls off. Once all the bolts are out and loosened, use the screw driver to pry the cover back. It will be a bit sticky from the last round of sealant that was used.
Which will leave you with this.
While the housing is draining go ahead and remove the calipers. There are 2 bolts holding them, and it takes a 10mm socket to get them off. Once removed just set them on the rear leaves, out of the way. Do Not leave them hanging.
Next you'll remove the rotors.
Spray a bit of PB blaster or WD40 onto the hub of the rear axle to loosen it up, then hit the back side of the rotor with the dead blow, or hammer and wood until it comes loose. At that point it will slide right off.
Now you are ready to move back to the differential to remove the center pin and c-clips, or if you have a tru trac, the assembly in the center of the carrier.
On the stock carrier use the 8mm socket to remove the bolt and then remove the center pin.
On a tru trac remove the snap ring. There are 2 pieces that will come out with snap ring. This will allow you access to the c-clips.
At this point, push the axle shaft into the housing to allow you to remove the c-clip. With either a large magnet or a pair of needle nose plier, remove the c-clips and set them aside.
Now, you can support the axle shaft and pull it straight out. Now would be a good time to inspect your shaft for any pitting or marks. If you have any, a fine piece of sand paper or emry pad will clean it up.
After my axle was removed further evidence of the leak was found
At this point I decided to clean out the housing of the old fluids and such prior to reassembling things.
I used a large pry bar to pop the seal out, here is the old seal and bar I used
At this point you'll want to clean up the area where the seal was at prior to installing your new seal.
Then using a dead blow install the new seal ensuring you get it flush
Next, slide the axle shaft back in and just reverse the process.
I used a small screw driver and hammer to tap the c-clips back into place.
At this point take your differential cover and using a gasket scraper clean all the old RTV off of it. Once all the large stuff was gone I used a wire wheel to clean up the rest of it.
Do the same to the housing
Apply a small bead of RTV to the cover and re-install the bolts.
Lastly its time to fill your diff. The owners manual calls for 2.7 liters of fluid or about 2.5 quarts.
the fill hole takes a 3/8" square drive to remove it.
When you get fluid just starting to dribble out you are done, re-install the plug, put your tires back on and set the truck down.
If you have any tools or helpers left under the truck, make sure they are out of the way... HAHA
