I went to a local Camaro show over the weekend. After about 40 miles of driving the rear in my car started acting funny. No problem driving straight but when I make a turn the rear starts to chatter and feels like it is locking up. I suspect it is the clutch pack in the rear any idea what might be wrong?

Thanks

Do you have the posi-gear oil additive from gm in the rearend? without it you will get the chatter.

The car sat for 17 years before I got it. I went over everything in the car but the rear because I had intended on replacing the rear. Finding the correct 12 bolt and having the money to do so is another issue. But the rear is the only thing I haven't done anything with. You think if I drain it refill and add the additive it may be okay?

Worth a try. If there is room, you might just add the bottle of additive to what you have now.

If this car sat for 17 years, I would drain the rear end and refill with only GM rear end oil and positraction additive. Cheap enough to do the job right. Get a new cover gasket also.

I had this headache yrs back...before the internet...and NZ doesnt have a lot of posi s lol

Tried all sorts of specia;ist limited slip diff oils additives etc...

The only stuff that works is the GM as mentioned above..

Diff cover gasket...dont need it
clean the cover and use silcone...not too much
smear thin grease on the diff gasket surface
bolt up but not full torque
leave for a few hrs, final torque up and fill

This gives a reusable gasket, stuck to the cover but not the housing

The car sat for 17 years before I got it. I went over everything in the car but the rear because I had intended on replacing the rear. Finding the correct 12 bolt and having the money to do so is another issue. But the rear is the only thing I haven't done anything with. You think if I drain it refill and add the additive it may be okay?

After you do the new diff. grease and additive...take it to a big open parking lot and bind the rearend both ways and get into the throttle a little bit. My car sat up for about two years while I was doing some restrore stuff and my 10 bolt posi had just been rebuilt.I just now got it running and first time out of the driveway when I turned to get on the street it acted like a live axle...literally rotating turn for turn with the outside tire.I called the guy who built it, and he's really good and known throughout my area.He told me to do just what I told you...that the clutches will act silly after sitting up sometimes.Well I did it and my rear gear is fine now, so just a thought

If changing the oil doesn't fix it then you might need to rebuild the posi. When the clutches wear they get to the point where the will pop and chatter even with good oil. It is also possible that some of the ears migt be broken off of the clutch discs and are spinning inside the differential. Try the oil first and give it some time to work it's way into the clutches.

Big Gear Head, what does a mildl built 12 bolt with 3.73's run. What does delivery cost. Not that I have the money now but just thinking ahead.

A new Moser 12 bolt starts at $1900. This gets you a new Moser housing, Eaton posi, 30 spline c clip axles, 1310 yoke and a chrome cover. Shipping is usually around $150 to $200. A rebuilt used rear end will not be much less that this and won't be as strong. The basic Moser 12 bolt is more than enough for most street/strip cars.

Thanks,that is not terrible. That will by my route if I can not find an original.

What about adding some of that Marvel Mystery Oil!!:D.....No, just kidding!.....The clutches are probably sticky and stuck from sitting all those years.....You may luck out if you drain, refill and add the additive also perform the "load" test to free up the clutches:thumbsup: