Need help for '77 rear diff cover change out
Thread Starter
Le Mans Master
Joined: Sep 2003
Posts: 8,934
Likes: 657
From: Norwalk ohio
2019 Corvette of the Year Winner
St. Jude Donor '15
Need help for '77 rear diff cover change out
Neighbor down the street has a '77 with the broken rear spring bolt tabs on the rear diff cover.
Looking at it, it is pretty obvious that the car body and leaf springs all sit on or attach to that rear diff cover.
Since he just got the car and I don't have any experience in this area, we need some help.
Where should we start? What would be the steps to changing this out? What should we look out for?
Thoughts, comments and photos would be a great help!!!
thanks, Herb
Looking at it, it is pretty obvious that the car body and leaf springs all sit on or attach to that rear diff cover.
Since he just got the car and I don't have any experience in this area, we need some help.
Where should we start? What would be the steps to changing this out? What should we look out for?
Thoughts, comments and photos would be a great help!!!
thanks, Herb
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,990
From: Connecticut, USA
Sure, first do a search and you'll find a lot of info on this job. The older books will tell you to remove the cover from the diff while it's in the car. This can be done but it is much harder and you stand the chance of dropping it on you.
I recommend removign the whole diff and then draining the oil, checking the yokes for play, and replacing the cover with a HD Muskegon one. If you do use the HD cover you may have to grind a small radius where the crossmember sits and also relief the spring where the 4 bolts go. I've had to do this with the HD covers I installed.
If you go to Carlisle next week stop over to my spot and I'll go over the job with you. I may even have a HD cover there.
Good luck
Gary
I recommend removign the whole diff and then draining the oil, checking the yokes for play, and replacing the cover with a HD Muskegon one. If you do use the HD cover you may have to grind a small radius where the crossmember sits and also relief the spring where the 4 bolts go. I've had to do this with the HD covers I installed.
If you go to Carlisle next week stop over to my spot and I'll go over the job with you. I may even have a HD cover there.
Good luck
Gary
Thread Starter
Le Mans Master
Joined: Sep 2003
Posts: 8,934
Likes: 657
From: Norwalk ohio
2019 Corvette of the Year Winner
St. Jude Donor '15
Originally Posted by gtr1999
Sure, first do a search and you'll find a lot of info on this job. The older books will tell you to remove the cover from the diff while it's in the car. This can be done but it is much harder and you stand the chance of dropping it on you.
I recommend removign the whole diff and then draining the oil, checking the yokes for play, and replacing the cover with a HD Muskegon one. If you do use the HD cover you may have to grind a small radius where the crossmember sits and also relief the spring where the 4 bolts go. I've had to do this with the HD covers I installed.
If you go to Carlisle next week stop over to my spot and I'll go over the job with you. I may even have a HD cover there.
Good luck
Gary
I recommend removign the whole diff and then draining the oil, checking the yokes for play, and replacing the cover with a HD Muskegon one. If you do use the HD cover you may have to grind a small radius where the crossmember sits and also relief the spring where the 4 bolts go. I've had to do this with the HD covers I installed.
If you go to Carlisle next week stop over to my spot and I'll go over the job with you. I may even have a HD cover there.
Good luck
Gary
what you described above is already more than either he or I thought....so I am glad I am asking someone that has done this before where to start.....I know we would screw something up otherwise.
Herb
thanks, Herb
Race Director
Joined: Apr 1999
Posts: 10,866
Likes: 717
From: Beverly Hills/Pine Ridge Florida
You need to remove the spring. (very carefully, as the potential energy stored can hurt you badly).
Then you remove the half shafts.
Then, uncouple the drive shaft and pull it forward.
Unbolt and remove the snubber and bracket on the front of the diff.
You'll likely have to remove the mufflers/exhaust system and the spare tire carrier and hardware.
Then,
take off the strut rod bracket, and possibly remove the strut rod ends from the bracket.
THEN, unloosen the bolts in the Lt. and Rt sombrero bushings. Get a big prybar, and pop the diff crossmember off the sombreros. (carefully). Use a floor jack to lower the entire assembly.
You'll then have the entire diff attached to the crossmember on the floor.
It's a MAJOR job. I've never tried to change one "in the car" by separating it from the diff itself, and trying to unbolt the four 5/8 bolts that hold the cover to the diff. crossmember. Chuck
Then you remove the half shafts.
Then, uncouple the drive shaft and pull it forward.
Unbolt and remove the snubber and bracket on the front of the diff.
You'll likely have to remove the mufflers/exhaust system and the spare tire carrier and hardware.
Then,
take off the strut rod bracket, and possibly remove the strut rod ends from the bracket.THEN, unloosen the bolts in the Lt. and Rt sombrero bushings. Get a big prybar, and pop the diff crossmember off the sombreros. (carefully). Use a floor jack to lower the entire assembly.
You'll then have the entire diff attached to the crossmember on the floor.
It's a MAJOR job. I've never tried to change one "in the car" by separating it from the diff itself, and trying to unbolt the four 5/8 bolts that hold the cover to the diff. crossmember. Chuck
Melting Slicks
Joined: Apr 2004
Posts: 2,083
Likes: 2
From: Montreal Qc.
Originally Posted by gtr1999
Sure, first do a search and you'll find a lot of info on this job.
http://forums.corvetteforum.com/show....php?t=1444162
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Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,990
From: Connecticut, USA
Originally Posted by firstgear
I will be at Carlise on that Saturday....where do I find you? Send me a PM on the HD cover cost...I can let my friend know if he wants me to pick one up for him or if he wants to order from Corvette America or other shop.
what you described above is already more than either he or I thought....so I am glad I am asking someone that has done this before where to start.....I know we would screw something up otherwise.
Herb
thanks, Herb
what you described above is already more than either he or I thought....so I am glad I am asking someone that has done this before where to start.....I know we would screw something up otherwise.
Herb
thanks, Herb
I'll be at L116-117 My firend has a HD cover that will work and will have it there, not sure what he wants for it but we'll be there Thursday afternoon to Sat. Stop and I'll go over the job with you.
Gary
