Can anyone identify this washer. It just fell out of my rear end when I removed the cover and emptied the gear oil. It is not flat, but rather slightly concave. Rear is a 12 bolt posi. Thanks!!

spider gear washer, needs to go back in!

spider gear washer, needs to go back in!

I'll second that.

Someone had an axle out and rotated the carrier. Make sure the posi case isn't torn up and put it back in. It goes between the spider gear and the case and can be a real bear to get in.

It could be a spare part left over from earlier work, but if you have such a washer missing from one of the spider gears you need to take a close look at it all to see if anything has been damaged.

If it has been run for a while with the thrust washer out then the case might be worn. All you can do is put it back and hope for the best. There is no way to repair the case if it has been damaged. There should be a thrust washer behind both of the pinion (spider) gears. Be sure that they are both in place before you put the cover back on.

It can't fall out unless the pinion shaft has been pulled. I bought a few spares from my local GM dealer a few years ago. They do crack in two and fall out occasionally. Not good for the gears especially if a piece goes up in between them. It would be a good idea to check the other one while you are in there. Cheap insurance.

I remember now that when i bought this rear end we pulled the axles out in order to remove the brakes!! The washer must have fallen out then because right before we pulled the rear i test drove the car and it was very smooth and quiet. The rear has been sitting in my yard for a year now but has not been used so I hopefully should be ok!!!

I'll check it in the morning. Thanks guys.....Todd (sweet64)

p.s. I should have pics up soon of my frame off resto 64 malibu!!

If you have a problem getting it back in, you can flatten it a little in a vise and then put it in, it won't hurt it, we have a guy here locally that does all this, is really sharp, told me how to do it.

Rob

These washers are hardened some to take the wear. They act as a bearing on the back of the spider gears. Flattening them is going to make a poor mating surface with the spider gears which are also dished. This will actually make them harder to install. The added stress could also lead to premature failure. The posi springs will be causing you grief in getting the washers/bearings back in. It's not much of a job to remove the springs.

I only go by what works, and the guy that does all this gear work has been at it a long time, he did my sons 12 bolt, 725 honest horse, we ran 456s and 373s and never ever had to have this guy rework anything, he does a lot of fleet trucks and high performance rear ends, and you're saying this won't work. And you can't get them back in there with out flatting them a little or tearing other stuff out.

Two differences of opinion here. We pounded this chevelle at the track and on the street for several years, and it hung in there.

Rob