Hey whats involve with replacing the upper and lower differential Cushion? Is it something  a novice can do?

Sure!! Not a big job at all.
Raise the rear of the car enough to get under it. Then remove the bolt the goes thru the cushion. The nut on top may be hard to get to, but if you take the rear u-joint loose from the diff. it will be much easier.
If your car(81 4speed) has the steel support bolted to it, loosen the two bolts going thru it and the diff. Then take the top bolt out(or both of them, if you want). The support will then come down, and the lower cushion too.
Then just fish the upper cushion out from the top of the frame, and reverse to assemble. Remember to install the two bolts on the steel support from the drivers side, with the nuts on the passenger side.

If you car has the lower support cast as part of the diff., then you will need to pry down on it to get the lower cushion out. This type of diff. is a little harder to get the cushions out of, but not that much. To tell the truth, the hardest part will be getting the u-joint loose! Pay close attention to how the cushions, and the washers/spacer fits, so you can put it back exactly the same way.

Here's a PIC of the different diffs, to give you an idea of how they are, just in case you need the info.Adams' Apple2006-12-31 20:29:06

i am glad i joined this site. i seen a simsilar thread posted as i do get a noise from rear. checked the universals and seemed to be all right. never thought about these cushions could be the culprit. thanks for saving me a lot of aggravation as i will be checking these too. eddie208752007-01-01 09:55:28

What a coincidence, I got my poly mounts in before the weekend and I plan on replacing them tomorrow 

Hey let me know how it goes I just order my cushions from Mid America.

Apple where did you get that digram? The one you sent is hard to read.

Not if you enlarge it!
If you click on the link, it sizes the pic to fit the screen. if you place your cursor(mouse) over the image, you will see either a little magnifying glass as your cursor , or a small box in the lower right hand corner. Click on the image with the mag. glass, or on the box in the corner, and it will enlarge the pic.

Dang...beat me to it...
If you are using IE browser, it will be a box in the corner that has arrows pointing out to all four corners. This will enlarge the picture.
If you are using Firefox, it will turn yoour pointer into a magnifuing glass. Thanx, Marty!

Apple your the man thanks.

Well my first attempt didn't go so well    Maybe someone can tell me the secret to getting the rear U-joint loose?  7mm is too big but 6mm is too small?  9/32 is too big but 1/4 is too small??  I was actually (somehow) able to remove the bolt and all the hardware with the driveshaft in place but it's just too difficult to work the mounts loose without getting the extra room in there.  If anyone has been able to accomplish this on an '82 without removing the driveshaft, I'l buy you a drink 

Hey Apple as I was driving to work this morning I remember that I have a 81 assembly manual.