Differential cover replacement
Thread Starter
Racer
Joined: Sep 2005
Posts: 260
Likes: 0
From: Wheaton Illinois
Differential cover replacement
The differential carrier rear cover is cracked on my 76, where the spring bolts to it. My Chiltons manual doesn't cover it's replacement. I plan on replacing it with a heavy duty cover.
I pulled the spare tire tub to get a good look. It looks preaty straight forward. Are there any pitfalls or problems I should be aware of before I start taking things apart.
Thanks.
I pulled the spare tire tub to get a good look. It looks preaty straight forward. Are there any pitfalls or problems I should be aware of before I start taking things apart.
Thanks.
Melting Slicks
Joined: Apr 2004
Posts: 2,083
Likes: 2
From: Montreal Qc.
You'll have to drop the rear crossmember, lots of threads in C3Tech on that, mostly how to break it loose once the bolts are out (tons of PBBlaster + three-arm puller seems to be the ticket). I have the same job to do, but I'm kinda dreading it, straightforward or not.
Then fill with the proper lube + posi-additive and work it in by doing figure-8s in a parking lot, that's been covered a lot on here too.
Then fill with the proper lube + posi-additive and work it in by doing figure-8s in a parking lot, that's been covered a lot on here too.
Instructor
Joined: Jan 2006
Posts: 166
Likes: 22
From: Colorado Springs Colorado
Dropping the cross member isn't as hard as it might sound.
Be sure to put a jack under the differential to support the weight. Once everything is detached from the differential, and you begin to remove the cross member bolts, leave the cross member bolts threaded in about 1/4 the way. that way when it does pop loose it won't just drop straight down. Then you can use a 2 or 3 jaw gear puller on each end of the cross member. Put the jaws on the outside of the crossmember bar and put the center bolt on the crossmember bolt and put a ratchet to it.
I tried a crow bar and pulled and pulled with no progress. Just alot of shaking on the jack stands. When I went to use the gear puller it popped off in a matter of seconds. Didn't need any PB blaster in there at all. Besides it might be corrosive on the rubber bushings.
good luck!
Swede
Be sure to put a jack under the differential to support the weight. Once everything is detached from the differential, and you begin to remove the cross member bolts, leave the cross member bolts threaded in about 1/4 the way. that way when it does pop loose it won't just drop straight down. Then you can use a 2 or 3 jaw gear puller on each end of the cross member. Put the jaws on the outside of the crossmember bar and put the center bolt on the crossmember bolt and put a ratchet to it.
I tried a crow bar and pulled and pulled with no progress. Just alot of shaking on the jack stands. When I went to use the gear puller it popped off in a matter of seconds. Didn't need any PB blaster in there at all. Besides it might be corrosive on the rubber bushings.
good luck!
Swede
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
Originally Posted by SwedeAWACS
Dropping the cross member isn't as hard as it might sound.
Be sure to put a jack under the differential to support the weight. Once everything is detached from the differential, and you begin to remove the cross member bolts, leave the cross member bolts threaded in about 1/4 the way. that way when it does pop loose it won't just drop straight down. Then you can use a 2 or 3 jaw gear puller on each end of the cross member. Put the jaws on the outside of the crossmember bar and put the center bolt on the crossmember bolt and put a ratchet to it.
I tried a crow bar and pulled and pulled with no progress. Just alot of shaking on the jack stands. When I went to use the gear puller it popped off in a matter of seconds. Didn't need any PB blaster in there at all. Besides it might be corrosive on the rubber bushings.
good luck!
Swede
Be sure to put a jack under the differential to support the weight. Once everything is detached from the differential, and you begin to remove the cross member bolts, leave the cross member bolts threaded in about 1/4 the way. that way when it does pop loose it won't just drop straight down. Then you can use a 2 or 3 jaw gear puller on each end of the cross member. Put the jaws on the outside of the crossmember bar and put the center bolt on the crossmember bolt and put a ratchet to it.
I tried a crow bar and pulled and pulled with no progress. Just alot of shaking on the jack stands. When I went to use the gear puller it popped off in a matter of seconds. Didn't need any PB blaster in there at all. Besides it might be corrosive on the rubber bushings.
good luck!
Swede
Now I need to figure out how to replace the pinion and oil seal, whatever those are....
Instructor
Joined: May 2006
Posts: 223
Likes: 1
From: Kennesaw GA
Correct, you just need to remove the diff cover bolts, and back the two crossmember bolts out about 3/4 of the way, then take the 3 jaw puller to the ends. Mine popped right off with no real problem.
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
All this is after you've removed the half and drive shafts, right? Once you get it down, how do you replace the seals on the sides?
What else do you need to replace besides the rear diff gasket (assuming the gears look fine)?
What else do you need to replace besides the rear diff gasket (assuming the gears look fine)?
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Melting Slicks
Joined: Apr 2004
Posts: 2,083
Likes: 2
From: Montreal Qc.
Originally Posted by 90ZR1
All this is after you've removed the half and drive shafts, right? Once you get it down, how do you replace the seals on the sides?
What else do you need to replace besides the rear diff gasket (assuming the gears look fine)?
What else do you need to replace besides the rear diff gasket (assuming the gears look fine)?
Jack up car, place jack stands under frame in front of rear wheels.
Take off spare-tire and carrier, and maybe some of your exhaust system (but probably no need to do that).
Remove spring-to-trailing arm bolts (the long things with the washers and rubber on them).
Support tires (or t-arms) so that the half-shafts are not hanging down/supporting the t-arms.
Unbolt spring from rear-end cover, get spring out of the way.
Drain rear end.
Support rear end with a jack.
Undo two crossmember bolts.
Undo diff cover bolts.
Drop diff and crossmember together <<<---that's the part that everyone says is a b****.
Hey guys, did I miss anything??
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Originally Posted by Star79
You don't have to take that stuff off, theoretically all you need is a new cover, fluid and gasket (but new bolts are a good idea).
Jack up car, place jack stands under frame in front of rear wheels.
Take off spare-tire and carrier, and maybe some of your exhaust system (but probably no need to do that).
Remove spring-to-trailing arm bolts (the long things with the washers and rubber on them).
Support tires (or t-arms) so that the half-shafts are not hanging down/supporting the t-arms.
Unbolt spring from rear-end cover, get spring out of the way.
Drain rear end.
Support rear end with a jack.
Undo two crossmember bolts.
Undo diff cover bolts.
Drop diff and crossmember together <<<---that's the part that everyone says is a b****.
Hey guys, did I miss anything??
Jack up car, place jack stands under frame in front of rear wheels.
Take off spare-tire and carrier, and maybe some of your exhaust system (but probably no need to do that).
Remove spring-to-trailing arm bolts (the long things with the washers and rubber on them).
Support tires (or t-arms) so that the half-shafts are not hanging down/supporting the t-arms.
Unbolt spring from rear-end cover, get spring out of the way.
Drain rear end.
Support rear end with a jack.
Undo two crossmember bolts.
Undo diff cover bolts.
Drop diff and crossmember together <<<---that's the part that everyone says is a b****.
Hey guys, did I miss anything??
Last edited by ...Roger...; Jul 14, 2006 at 11:35 PM.
Instructor
Joined: Jan 2006
Posts: 166
Likes: 22
From: Colorado Springs Colorado
I removed the half shafts before I attempted to drop the differential.
The differential and the crossmember come off in one complete assembly. You'll have to do this in order to get to the 4 x bolts attaching the differential to the cross member.
Again, keep the cross member bolts in at least a 1/4 turn remaining so when you pop it loose with the gear puller it won't come crashing down. Once both sides of the crossmember are loose, then support the entire assembly with a floor jack. Then remove the 2 x cross member bolts and lower the assembly to the floor.
Now you'll be able to see the access holes on top of the crossmember that were hidden by the body. Remove those 4 x bolts to separate the crossmember from the differential.
I think this process was relatively painless and actually pretty simple. But I had just previously tackled the trailing arm removal process with the sawzall.
After you take on the dreaded "rusted trailing arm dillema", everything else now seems simple.
Good luck
Swede
The differential and the crossmember come off in one complete assembly. You'll have to do this in order to get to the 4 x bolts attaching the differential to the cross member.
Again, keep the cross member bolts in at least a 1/4 turn remaining so when you pop it loose with the gear puller it won't come crashing down. Once both sides of the crossmember are loose, then support the entire assembly with a floor jack. Then remove the 2 x cross member bolts and lower the assembly to the floor.
Now you'll be able to see the access holes on top of the crossmember that were hidden by the body. Remove those 4 x bolts to separate the crossmember from the differential.
I think this process was relatively painless and actually pretty simple. But I had just previously tackled the trailing arm removal process with the sawzall.
After you take on the dreaded "rusted trailing arm dillema", everything else now seems simple.
Good luck
Swede
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
OK, I'm going to have to remove the exhaust sys, the tie rods and everything because I'm going to have to get the whole diff out.
Once it's out, I need to replace the diff rear gasket and both side seals.
So what's involved in doing those side seals? How do you do that? (Is that what they're called?) Does the local parts shop carry them?
Once it's out, I need to replace the diff rear gasket and both side seals.
So what's involved in doing those side seals? How do you do that? (Is that what they're called?) Does the local parts shop carry them?
Racer
Joined: Jun 2004
Posts: 384
Likes: 0
From: freehold NJ
I actually (finally) dropped my differential and cross member last night. I pulled the cover off the diff. Not sure where to go from there. Meanwhile, I have a lot of cleaning to do in that rear diff area on the car. I also have to put the new bushings in the strut rods. (Yes, I finally got those out too).
I have to figure out how to get the side yokes out of the diff now.
So let me know how your progress goes.
I have to figure out how to get the side yokes out of the diff now.
So let me know how your progress goes.
Instructor
Joined: Apr 2005
Posts: 203
Likes: 20
From: Madison Indiana
Wow, all that just for the differential cover?!? Obviously I haven't spent much time under my car yet.
So, if I just wanted to replace the gear oil, how is that done? Is there both a drain and fill plug?
Thanks!
So, if I just wanted to replace the gear oil, how is that done? Is there both a drain and fill plug?
Thanks!
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by Allen_396
Wow, all that just for the differential cover?!? Obviously I haven't spent much time under my car yet.
So, if I just wanted to replace the gear oil, how is that done? Is there both a drain and fill plug?
Thanks!
So, if I just wanted to replace the gear oil, how is that done? Is there both a drain and fill plug?
Thanks!
