Help with '81 differential carrier
Thread Starter
Racer
Joined: May 2003
Posts: 375
Likes: 0
From: LaSalle ON
Help with '81 differential carrier
I am in the process of buttoning up the rear suspension after my broken half-shaft fiasco. I have bolted the differential carrier to the case, but the ends with the rubber bushings are about 1" behind the U-channels they should fit in at either end! Nothing seems to want to give to make it fit. I tried leg-pressing the differential forward, but no-go. Should I loosen the bolt on the differential case, or will this help? 
Any suggestions (except re-locate and weld the brackets on the frame
) would be appreciated.
Thanks.
[Modified by vettenoir, 12:19 AM 6/27/2004]
Any suggestions (except re-locate and weld the brackets on the frame
) would be appreciated.Thanks.
[Modified by vettenoir, 12:19 AM 6/27/2004]
Melting Slicks
Joined: May 2002
Posts: 2,508
Likes: 0
From: Wisconsin
Re: Help with '81 differential carrier (vettenoir)
I'm confused as to what you are talking about. Are you talking about the differential crossmember with the rubber cups that bolt to the frame? Or are you talking about the strut rods and their bracket on the differential cover? Or is this something inside the differential itself?
[Modified by Schmucker, 1:32 AM 6/27/2004]
[Modified by Schmucker, 1:32 AM 6/27/2004]
Thread Starter
Racer
Joined: May 2003
Posts: 375
Likes: 0
From: LaSalle ON
Re: Help with '81 differential carrier (Schmucker)
I mean the big aluminum cross-member piece with the rubber cups on the ends. On an '81, the the part is referred to as the differential carrier and/or cover in the service manual. (See signature as to why I'm asking about an '81 part when I list the car as a '77...)
Bob
[Modified by vettenoir, 8:31 AM 6/27/2004]
Bob
[Modified by vettenoir, 8:31 AM 6/27/2004]
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: Help with '81 differential carrier (vettenoir)
I think the rear crossmember may not be semitrical. It could be possible to bolt the diff to the crossmember backwards. Then when you lift the assembly up there it wont line up. I know the crossmember on my 73 is that way. Its possible to bolt the diff on backwards, then the crossmember wouldnt line up with the frame. The bolt holes for the diff to member and member to frame are not centered with each other. The member could be backwards. Just a guess.
Pro
Joined: Sep 2002
Posts: 690
Likes: 1
From: near Memphis TN
Re: Help with '81 differential carrier (vettenoir)
Hmmm, most of us (including me) would take out the differential, housing and carrier and all, outright and not remove the cover with it in the car. Did you remove the cover and crossmember and leave the differential in the car?
If so I think the problem is that the differential is leaning down in back without the support of the crossmember (it's attached to the frame in front) and you need to get a jack under it to bring it up parallel to the frame and then it should be in place.
Another thing to think about is, if you did undo the bolts or u-joints on the front of the differential, is that you no longer have it lined up correctly with the drive shaft.
If so I think the problem is that the differential is leaning down in back without the support of the crossmember (it's attached to the frame in front) and you need to get a jack under it to bring it up parallel to the frame and then it should be in place.
Another thing to think about is, if you did undo the bolts or u-joints on the front of the differential, is that you no longer have it lined up correctly with the drive shaft.
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Help with '81 differential carrier (SpyderD)
if you removed the batwing you can never get it back in with the pinion bolt in place because you have to angle the diff then and the channels are just wide enough for the batwin bushings to slide in. The diff must be installed wing first, then pinion.
For those wondering what he's talking about:
For those wondering what he's talking about:
Thread Starter
Racer
Joined: May 2003
Posts: 375
Likes: 0
From: LaSalle ON
Re: Help with '81 differential carrier (Twin_Turbo)
Twin Turbo, Thanks for the advice I'll try it out tomorrow evening and see how I make out.
For those wondering... The reason I had the cover off without removing the entire differential was that the old one was smacked by a half-shaft and broken into 2 pieces about 40' into a launch at the dragstrip
Note: Breaking the cover into 2 pieces makes it very easy to remove it without removing the entire differential.
Thanks again!
I'll try it out tomorrow evening and see how I make out. For those wondering... The reason I had the cover off without removing the entire differential was that the old one was smacked by a half-shaft and broken into 2 pieces about 40' into a launch at the dragstrip
Note: Breaking the cover into 2 pieces makes it very easy to remove it without removing the entire differential.
Thanks again!
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Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: Help with '81 differential carrier (Twin_Turbo)
After looking at the pic Twin Turbo posted the 81 i see the 81 setup is obviously different than my 73. I now see my suggestion about the diff being on backwards is totally impossible. I was thinking the 81 might be like the 73. Sorry for the bogus reply.
Thread Starter
Racer
Joined: May 2003
Posts: 375
Likes: 0
From: LaSalle ON
Re: Help with '81 differential carrier (Twin_Turbo)
I removed the drive shaft and loosened the pinion bolt enough to get some end play in the differential housing. With combination leg press from the rear and manipulation of the jack supporting the differential, I managed to pop the 'batwings' back into their brackets. 
No
was even required to get the bolts in
Now to finish re-installing the rear suspension... oh, and replace the driveshaft U-joints which look like they've seen better days....
Thanks again
Jvette73,
No problem with the reply
Owning a car that is just about an even combination of '77, '81 and custom parts, I have messed up quite a few times due to differences between different years. If my entire car was a '77, the rear suspension would be the same as yours. (as far as I know...)
No
was even required to get the bolts inNow to finish re-installing the rear suspension... oh, and replace the driveshaft U-joints which look like they've seen better days....
Thanks again
Jvette73,
No problem with the reply
Owning a car that is just about an even combination of '77, '81 and custom parts, I have messed up quite a few times due to differences between different years. If my entire car was a '77, the rear suspension would be the same as yours. (as far as I know...)
