Gears & Axles - Think I found the reason for popping sound...

I have been having a popping sound somewhere in the rear only when I turn to the left, and have the clutch engaged. It has been slowly getting worse, and I was getting really tired of it. I've triple checked all the bolts back there (lca bolts, TA bolts, sway bar end links, etc.) and everything seemed fine. Well, today I go to take off the differential cover, and as the gear oil is oozing out, I can hear and see pieces of metal coming out. I drained all the oil, and I visually inspected the gears and none of them are chipped or missing pieces. I have an auburn rear, where could these pieces of metal have come from? Can I just replace the broken part and move on? Any ideas?

This would be a great excuse to get a 12 bolt or 9 inch, but I simply don't have the money to buy one at the moment.

After fishing out all the metal shavings in the gear oil, it looks to be a total of about 10-15 grams. Anyone have any idea what might have broken in there? Like I said, the ring and pinion gears look good.

Sounds like it's time for another differential. :( Explains why you heard it only turning left. Can't the Auburns be rebuilt?

I'm thinking/hoping it can be rebuilt or replaced. Is there any way for me to take out the broken parts in there and install new ones? I guess I'm just trying to be optimistic about it. Can this be done?

Doubtful. It might can be sent back to Auburn for a rebuild, dunno. You could always replace it with a cheap Torsen.

Krab. There are tons of these things FS on Ebay--both Auburn's and Torsen's. That a factory Auburn? '98 car? Or a SLP option Auburn carrier? You got the aluminum AAR cover on the rear? WJ

I have/had a factory Auburn, '00 f-body. The cover is an aftermarket T/A cover with the stud kit installed. The studs and preload bolts are also torqued down correctly. So I can just replace the Auburn with a zexel torsen and be done with it? I'll check ebay to see how much they run for.

OK, you have the SLP option rear axle---unless it had been previously changed. Just this morning in "differentials and parts" section of Ebay there were a bunch....Also, call SLP, they had a bunch of Torsen brand new take-outs they were selling for $100 each. Both Auburn and Torsen use the 28 spline axles. Buy a major overhaul kit (ebay) as well. Do the bearings and all. Check your ring and pinion gears for sharpness, nicks, etc. Was the rear howling or whining at all? Torsen's are stronger drag race carriers than Auburns anyway. (stock for stock). Best wishes. Hav-A-Tampa can probably add something to what I've said..... Best of luck. WJ

Thanks for the help, you guys are great. It looks like this is what I'll be doing to fix my rear. The rear was not howling or whining at all. This problem just started happening one day. I know it was because of track use, but I guess it took a while to see the full effects of it. I'll call SLP tomorrow to see if they have anymore torsen units. Is there anywhere else I can buy an overhaul kit besides ebay?

Anyone who sells ring and pinion sets sells the overhaul kits. Try to buy a USA made one. Also, buy a Ratech # 4111 solid crush sleeve and install it instead of the one in the overhaul kit. You can buy it from Strano, or another board sponsor--they're less than $20, and will help keep things in one place. The solid crush sleeve sets pinion bearing preload--not pinion depth. Also, when you've got your axles out, check the splines real close, and the narrowest and thinnest part of the axles real close....make sure there's no sign of any "twisting" or cracks, or anything else that looks funny. If you had the extra $, I highly reccomend the Moser HD C-clip axles--$225 pr. if you've got a 3 channel rear. Keep us posted how you make out and good luck. WJ

One last question, how do you physically take out the auburn unit? I've already got the main bearing caps off, but the auburn doesn't want to budge. Am I missing something to take it off?

Big prybar, or big screwdriver--it's a fairly snug fit. Don't be afraid of it--you won't hurt anything--just make sure you catch it! Although it is junk...... It's got to be shimmed fairly snug when putting the new one in, also. You'll need different shims for Torsen, if you go that route. You should have to tap the new carrier in w/good size mallet or hammer if it's shimmed properly for preload. WJ

Also make sure you have the axles out before prying on the diff. :jest: Here's a good site with pics showing how to take a rearend apart and put it back together. The Auburn has a different way of locking the axles in place than what's in the pictures, but they both use c-clips. This site is tearing apart an 8.5" 10 bolt and we have a 7.5", but it's very similar, ours is just smaller.

http://www.fullsizechevy.com/fscu/axletech/

That site is useful HavATampa. Do I have to measure for anything (backlash) if I'm not even touching the pinion gear and reusing the ring gear on the new torsen? How about the shims?

You guys have been extremely helpful to a beginner who's doing this for a first time. :cheers:

Need to check the backlash on the gear set now and try to get it back to that when you install the new diff. Also, make sure when you pop the diff out you keep the side shims marked for which side they came out of.

Good chance shim pack will need to be different when switching from Auburn to Torsen.....This is very important....WJ

Where can I get some of these shims and how do I know which ones to use? I didn't check backlash before I took off the carrier either. I'm guessing I can rent the measuring tool at an autoparts store?

I forgot to mention that the torsen I'm buying also comes with the shims used in the car it came off. Do I still have to get different ones because I'm changing out the ring gear, or can I just toss it all in there?

No, can't just toss it in...Get some help down there IN PERSON from someone knowledgeable who has done this job before w/success, otherwise you're going to end up doing it over, and maybe ruining the stuff you just bought. (Just my opinion.) Best of luck. WJ :bomb:

Krab: RU near Plano, at all? If so, I know a guy down there you could contact.... WJ

I'm about 7 hours from Plano. :( I don't know anyone down here who's done this type of work either. I guess I'll just have to do some serious research before I attempt tackling this whole backlash deal. Thanks for the advice WJ.