noisy Auburn

[c4racer]

I have a Auburn in a 8.5" rear under my 69 Camaro. The diff was set up with the new posi 3-4 years ago and has maybe 3K miles, all street. I am not sure if they used the pro or the regular series.

The concern I have is it makes a lot of racket - grinding noises etc. when doing slow corners, especially in parking lots. Reminds me a little bit of the locker I had in a 9" in a previous car. I used the regular Auburn in another 9" in one car I had and never noticed any strange noises. Backing up is the worst.

I tried changing fluid - I put a mix of redline NS and normal 75W90 gear oil. I may have to try 100% normal fluid with more of the LSD friction modifiers and see if that helps. The previous swap didn't change things much if any. Everything looked OK to the naked eye while I had the rear cover off btw. No excessive metal shavings either.

Could that be normal operation for a pro series Auburn?

[Jimi G]

Try 100% fluid with more friction modifier, I think that will help with the noise.

[Madspeed]

Auburn is the worst diff EVER made
do your self a favor and replace it with an eaton clutch pack style.

Or send it back to auburn for thier prorated warrenty.

[Midnight68]

I would have to disagree that Auburn is the worst diff made, My Auburn works great and has never made any noise. I have one in my 68 with an 8.5 and before that it was in another car. It probably has 50,000 miles on it and it works better than the brand new Eaton I used to have that mabye had 6,000 miles on it and only locked both wheels when it was in a good mood and that didnt happen to often.

[ItalianBullitt754]

My Aburn is noisy but not Grinding noisy only makes noise when high speed cornering. Make sure you have enough Traction modifier in it to keep it quiet.

[c4racer]

I will try 100% of the Redline with the friction additive and see if that helps. I should not have to add more additive - that would tell me something is wrong.

[ItalianBullitt754]

Auburns just love them some traction modifier. Don't know why.

[ItalianBullitt754]

I've got 2 quarts of Royal Purple Max Gear that has a traction modifier base along with Ford traction modifier and the modifier that came with the Auburn. Thats 2.5 quarts to match my Trick Flow Aluminum girdle cover. Seems like allot but it seem to work also.

[Madspeed]

I would have to disagree that Auburn is the worst diff made, My Auburn works great and has never made any noise. I have one in my 68 with an 8.5 and before that it was in another car. It probably has 50,000 miles on it and it works better than the brand new Eaton I used to have that mabye had 6,000 miles on it and only locked both wheels when it was in a good mood and that didnt happen to often.

Your a lucky sole.
I worked for 2 years at an offroad shop I did about 2 gear swaps a day on average but that is just my observation.
Now I onley setup about one a month.

[HILROD]

I used redline friction modifier in one and it acted like there still was none in it, so I added GM stuff and it quieted right down. FRANK