Im about to replace the pumpkin in my 89,as this is a first attempt and will be a one man job,has anyone tips or preferably a step by step process(pic's??) including carrier cover torque setting and the tightening sequence that may assist.:

 

It is a pretty straight forward job. Myself - I was doing other work while I had the rear end out so I bolted the pumpkin to the carrier(batwing) filled it with fluid and then installed it as an assembly. The thing is heavy so you may want to some extra hands to help. The whole trick is to get the car high enough. Check or replace the all shaft's u joints and transmission output yoke seal while you have it all apart.

 

Can this be accomplished using only car stands,or is a hoist the only way as I agree clearance and safe room to work is going to be a concern.
Replacing uni's and hubs at same time.

 

Sorry no pics of the event that was a long time ago.

I put my car up on a trailer so I had about 2.5 - 3 feet of wiggle room between the car and the ground this way. Jack stands might get you close to the short side of 2 feet clearance which might be enough....don't get crushed under there.

 

Twelve ton jackstands. They extend to 30 inches, and the broad base is very secure. I pulled the transmission on that jack and rolled it right out the rear, and vice versa.

 

Depending on what you are servicing, you will need 4 good jack stands and 2 floor jacks or 1 floor jack and a trans jack.
The car needs to be up in the air about 16" min. (front and rear),
Remove rear tires (although the job can be done w/out removing them)and remove the exhaust,
Support trans .w/either a floor jack or trans jack.
You will remove spring (mark order of shims and left and right side), remove h.shafts, disconnect lower camber arms at the rear end (bat wing)and pull down, disconnect upper tie rod ends at the top of the bat wing and pull them away from the rear end.
I put the trans jack under trans and take a little of the weight off, support the rear under pumpkin w/floor jack (taking a little weight off it) and remove C beam, then disconnect upper b.wing bolts and remove.
Reverse process to re-instal, the torque sequence and t. specs. are in your FSM.

 

I'm actually on the verge of changing the center section in mine. Wondering if it can be done without removing the batwing. Even if you do drop the batwing, why is it necessary to remove the spring? Is it in the way of any bolts?

 

[QUOTE=mseven;1570183239]Depending on what you are servicing, you will need 4 good jack stands and 2 floor jacks or 1 floor jack and a trans jack.
The car needs to be up in the air about 16" min. (front and rear),
Remove rear tires (although the job can be done w/out removing them)and remove the exhaust,
Support trans .w/either a floor jack or trans jack.
You will remove spring (mark order of shims and left and right side), remove h.shafts, disconnect lower camber arms at the rear end (bat wing)and pull down, disconnect upper tie rod ends at the top of the bat wing and pull them away from the rear end.
I put the trans jack under trans and take a little of the weight off, support the rear under pumpkin w/floor jack (taking a little weight off it) and remove C beam, then disconnect upper b.wing bolts and remove.
Reverse process to re-instal, the torque sequence and t. specs. are in your FSM.
Thanks for the pic's
seems Getting it off the ground to a workable safe height will be the interesting bit and biggest hassle.

 

You have to place the jackstands at the normal jacking points, so obviously you can't jack there.

The front of the car is much heavier than the rear. Raise the front first, placing the jack under the center of the crossmember at the front of the engine.

On my model the exhaust prevents jacking the rear in the center, so I place the jack where the strut rod attaches to the knuckle as close as possible to the wheel. The rear of the car is so light that you can raise the entire rear from one side.

I do it in several steps, first just getting the stands under there, then raising them to where I want them.

 

It can probably be done that way, but dealing with lack of room, cleaning the silicon and trying to line it up etc. might be a PIA.
Again it depends on what you servicing...the spring could stay on but make sure the car is up in the air high enough to clear the spring after it has no tension. When the entire diff. is removed, seperating the chunk from the wing it may get in the way other than that I don't see why not.

Something I forgot to mention, when removing the spring I take a piece of wood (2x4x about 1') place it on the jack and take some pressure off the spring/height adjustment bolt. Remove the height adjust bolt then lower the jack (do the same on the other side.).

 

About to drop the rear,progressing slowly..down to removing c beam(whats the secret on accessing the nuts located on top of the C beam??)
as Im doing rear hubs,uni's as well as replacing the pumpkin,is it easier to drop the whole assembly rotor to rotor? replace pumpkin first,do uni's and replace rear wheel hubs last??
Also What's the Size of the spindle nut,trying to find a socket that fits.

 

36mm for the spindle nut. As far as the c beam nuts I think that is a 23mm wrench and skinny arms.

 

This is the way that I do it.

1. Remove both rear tires.
2. Lower rear leaf spring pressure on spring bolt.
3. Remove rear leaf spring.
4. Disconnect Axle outer socket on axle tie rods, from suspension knuckle.
5. Disconnect halfshafts at pumkin axle shaft.
(Tape up u joint as you remove it)
6. Disconnect drive shaft at pumkin
7. Support transmission.
8. Remove c beam bolt at pumkin and transmission.
9. Remove parking brake support clip in c beam.
10. Slide drive shaft and c beam forward.
11. Remove spindle rod bolts at bat wing and move out of way.
12. Support bat wing.
13. remove bat wing bolts.
14. Lower bat wing.
15. Replace pumkin.

Thats pretty much how it goes.

 

You don't have an ounce of dirt or grease on that car do you? It's clean enough to eat off of.

 

lol....yeah I guess it's pretty good....just part of the sickness, and don't want to work in a gease pit.
I have been through the car pretty extensively and it only gets driven on nice days. When I snap this 44 I will be doing what you did, probably a ford diff.

 

I was actually just going to comment on how clean the underneath of that car is.

I would post pics but after seeing those I would be embarrased when I posted pics of my dirty greasy car.



Anyway I would not suggest tring to do this job with leaving the spring in the car. Stick a jack under a side of the spring, undo the retaining nut on that side, lower the jack (end of the spring will come with it) and repeat for the other side. When both sides are dropped undo, the mounting pad bolts and pull that spring right out of there, its not near as scary as it may first look.

Looking back I think the area that gave us the most trouble was the cbeam, getting wrenches on it and getting it out of the way was a pita. Although the hour was late and the beers were plenty by that point.

Only other hitch I ran into was a bad front pinion seal (yes I found it the hard way). After completing the swap and getting it on the road it started puking after about a 20 min drive. Had to pull down the exhaust , driveshaft and change it out. (Moral of tha story is if its a used diff - change the seals while its sitting on your workbench looking pretty cause its alot easier then doing it when its installed in the car.)

 

A couple of gimmicks that I find handy which may help other members...

When assembling anything that needs lining up, take a couple of long bolts and cut the heads off. These will then screw into the (for example) pumpkin and slide though the holes in the batwing. Really helps with a heavy object, leaving hands free to do other work.

For cleaning up gasket surfaces, go to the welding supply and get cleanup wheels. These look like little grinding wheels only they are very coarse scotchbrite. They come in different diameters and texture. Then are intended to be used with a die grinder to clean up rusty metal, but I use them with a slower speed right angle drill. Saved me a lot of time and effort preparing the block for a new water pump. It should do well on the differential also.

Alignment dowel...



Last time it was apart...



Plenty of room, stands were almost all the way down. Should have done the differential "while I was in there" <groan>

 

Take a look at the thread Tachout's Project.

http://forums.corvetteforum.com/c4-t...s-project.html

There are some pictures of mine out of the car. I already had the engine out. But here is how I would do it if I were just doing the Diff.

I would start by Putting the car on Jack Stands as high as I could
Pull the rear tires
Remove calipers, and tie them out of the way
Remove the Speed sensors and tie them out of the way.
Remove the C-Beam
Remove the drive shaft
Remove the bolts that hold the control arms to body (3 Each Side and leave the control arms attached.
Support the Diff with a Floor Jack
Remove the bolts holding the bat wing
Carefully lower the bat wing out from under the car, avoiding the E-Brake Cable running across the car.
Now that it is out of the car, it is easier to work with, and gives you a chance to clean and inspect everything. Replace all rubber in there if time and cash allows, and allows you to make it all clean and leak free before it goes back in. Also give you a chance to replace those axle ujoints as this is the perfect time to do it.

In replacing the rear pumpking make sure that one your putting in has new seals all the way around. If you look at this thread, it has a pic of where the bolts are and the sequence of tightening them and the torque specs:

http://forums.corvetteforum.com/c4-t...dana-36-a.html

Hope this helps. If you need any further help, or pictures, let me know and I will help where I can.

 

Thanks for the offer tachout,I may just have to take you up on that
And thanks to the rest of you guys for the advice.

 

First time rear end out all good except copule of hiccups.,c beam was the biggest pita .I could not remove it until I slid the rear end out,Slid it forward and back,pushed off to the passengers side as well,and even with the drive shaft out .no go. wish finaaly I had small hands to access the top nuts,
Also Forgot to loosen the spindle nut until I was half way thru so will have to replace rear hubs when I get it back on wheels.
can I reuse the old lock washer on the spindle nut?