Rear diff front seal leaking

[fast4popper]

Oh, and I have over 70,000 miles on this drop since

2007... So if 45 mins is all it takes to change that 10$ seal, well worth it IMO

[f1ss]

It has indeed very much sir, thank you. I don't want to make a big deal but going through some health stuff so any inffo is helpful as my truck has sat a couple years. Thank you for the response sir.

-A

[MID12sSSS]

Rear pinion seals are gravy, but they can be tricky. The correct way is to remove rear tires and brakes, then measure pinion preload before you pull the rear pinion flange, that way it goes back correctly with the same (slightly more) preload, otherwise the inner sleeve can get crushed, starving the bearings of fluid, and roasting the rear diff. I didn't take the time to read all the above posts, so I'm sure someone answered your question already. But if you are to do it yourself, it can be done. It's just a little risky. Start by removing the 4 rear bolts cradling the rear u-joint on the drive shaft. Be sure to mark with a crayon the relation to the driveshaft hoof to the rear pinion flange so when you assemble it, it goes back together the way it came apart. Use a pry bar behind the hoof and hit it with a hammer to separate it from the flange. Leaving 1 bolt halfway in will keep the shaft from falling on your head while you knock it loose. You can either bungee the shaft up out of the way, or pull it out of the transfer case. Either way is fine. Then you need to remove the flange. To do this, you'll need a 2 jaw pulley puller. The nut can be removed with an impact gun, although that is not the correct way to do it. Lol. Mark a straight line across the nut, marking its correlation onto the shaft. Then remove the nut. Once the nut is removed, mark the correlation of the flange on the shaft, so it'll go together correctly. Use your 2 jaw puller to remove the flange. Then use a seal puller to pull on the TOP of the inside of the seal. Whenever I do a seal, I pull from the top, that way if I accidentally gouge the sealing surface, it won't leak. If you don't have a seal puller, sneak a flat tip screwdriver or gasket scraper between the seal and the pinion surface of the diff case. Tap it lightly with a hammer to pry the seal away from the diff. Work about 1/2 of the seal out and either punch it out at an angle, or grab it with vise grips and pull. Clean up the old surface with a razor blade and wipe with a clean rag. Put a coating of Vaseline around the sealing surface of the new seal and set into the pinion opening. Use a seal race and punch to install, or tap around the seal with a small hammer, seating the seal in evenly. Once the seal is completely seated, put the flange back up onto the shaft coming out of the seal, making sure your lines you scribed earlier are lining up. You'll need to tap the flange onto the shaft with a rubber mallet just far enough so you can start the rear pinion nut. And again, the is not the "correct" way to do this, but with a 1/2" impact gun, start rattling down the nut to suck the flange back into the shaft. Once the flange bottoms out, tap the trigger 2 more times, then the flange is seated. Once the nut is tightened, the nut should be slightly passed the lines you scribed earlier. It should be just slightly tighter. Only about 1/8" of an inch. That's about where you wanna be. While using an impact could potentially crush the inner pinion sleeve, its unlikely. It takes a good amount of pressure. I've seen it done a few times, but it's because the tech was rattlng on his impact for 5 minutes. Lol. Anyway, from here on out, just put the driveshaft back, lining up all your marks, and loctite your driveshaft u joint bolts. Top off fluids and your done. If you don't wanna take the risk doing it yourself, the book time is about 1.7hrs. So expect to pay just over $200 to get it fixed. So it's not too bad. Anyway, that's my .02 Lol.

Edited October 29, 2013 by MID12sSSS (see edit history)

[D1SCSS]

Nice write-up Brandon!!!!

[Downeast Johnny]

Nice write-up Brandon!!!!

 

^^ X2. Thanks Brandon.

[Brentd]

Rear pinion seals are gravy, but they can be tricky. The correct way is to remove rear tires and brakes, then measure pinion preload before you pull the rear pinion flange, that way it goes back correctly with the same (slightly more) preload, otherwise the inner sleeve can get crushed, starving the bearings of fluid, and roasting the rear diff. I didn't take the time to read all the above posts, so I'm sure someone answered your question already. But if you are to do it yourself, it can be done. It's just a little risky. Start by removing the 4 rear bolts cradling the rear u-joint on the drive shaft. Be sure to mark with a crayon the relation to the driveshaft hoof to the rear pinion flange so when you assemble it, it goes back together the way it came apart. Use a pry bar behind the hoof and hit it with a hammer to separate it from the flange. Leaving 1 bolt halfway in will keep the shaft from falling on your head while you knock it loose. You can either bungee the shaft up out of the way, or pull it out of the transfer case. Either way is fine. Then you need to remove the flange. To do this, you'll need a 2 jaw pulley puller. The nut can be removed with an impact gun, although that is not the correct way to do it. Lol. Mark a straight line across the nut, marking its correlation onto the shaft. Then remove the nut. Once the nut is removed, mark the correlation of the flange on the shaft, so it'll go together correctly. Use your 2 jaw puller to remove the flange. Then use a seal puller to pull on the TOP of the inside of the seal. Whenever I do a seal, I pull from the top, that way if I accidentally gouge the sealing surface, it won't leak. If you don't have a seal puller, sneak a flat tip screwdriver or gasket scraper between the seal and the pinion surface of the diff case. Tap it lightly with a hammer to pry the seal away from the diff. Work about 1/2 of the seal out and either punch it out at an angle, or grab it with vise grips and pull. Clean up the old surface with a razor blade and wipe with a clean rag. Put a coating of Vaseline around the sealing surface of the new seal and set into the pinion opening. Use a seal race and punch to install, or tap around the seal with a small hammer, seating the seal in evenly. Once the seal is completely seated, put the flange back up onto the shaft coming out of the seal, making sure your lines you scribed earlier are lining up. You'll need to tap the flange onto the shaft with a rubber mallet just far enough so you can start the rear pinion nut. And again, the is not the "correct" way to do this, but with a 1/2" impact gun, start rattling down the nut to suck the flange back into the shaft. Once the flange bottoms out, tap the trigger 2 more times, then the flange is seated. Once the nut is tightened, the nut should be slightly passed the lines you scribed earlier. It should be just slightly tighter. Only about 1/8" of an inch. That's about where you wanna be. While using an impact could potentially crush the inner pinion sleeve, its unlikely. It takes a good amount of pressure. I've seen it done a few times, but it's because the tech was rattlng on his impact for 5 minutes. Lol. Anyway, from here on out, just put the driveshaft back, lining up all your marks, and loctite your driveshaft u joint bolts. Top off fluids and your done. If you don't wanna take the risk doing it yourself, the book time is about 1.7hrs. So expect to pay just over $200 to get it fixed. So it's not too bad. Anyway, that's my .02 Lol.

Even more detailed than my explanation, and as such it is even more correct than mine. Good write up, guy on youtube bored a hole in a 2x4 to slip over pinion so you can bang on it to seat the seal. I made on of my own and it is very handy, not a big fan of banging on the seal with a hammer so this gave me a little sense of security that i wasnt damaging the seal.

[MID12sSSS]

LOL. Yeah. Like I said, it's not the "by the book" description if how it's done. That's a lot more involved and you need special tools etc. But if you were gonna give it a try on your own in your garage, you gotta work with what you've got. But like I said, if you're worried about ruining something, go get a quote for a rear pinion seal. Your probably won't be out much. My guess would be about $220 or so. But, if you can do it yourself, the seal is only like $14. Haha so big difference there.

[Brentd]

Oh yeah. This isnt one of those things that anyone should be too afraid to do. Really marking everything prior to disconnecting is the most important part. Removal and replacement is the no brainer part.

[sprayed99]

Just an FYI there is 2 seals on the front. One is the pinion, the other is on the collar. The collar seal doesn't usually go bad. I just wanted you to know it is there and they can fail.

[MID12sSSS]

Just an FYI there is 2 seals on the front. One is the pinion, the other is on the collar. The collar seal doesn't usually go bad. I just wanted you to know it is there and they can fail.

Good addition.