Did I break it?

[theMonch]

A couple of night ago I powerbraked the car for a little wheelspin action and let her go at about 5psi after 2-3 seconds of standing still and let it spin out for 20-30 feet and let off.

Now here is the problem. Ever since the car feels funny in the rear end. It squeals and feels like it is binding up on slow left hand turns, but not right hand turns. Additionally at highway speeds, It fells fine under a normal driving load, but when I let off of the accelerator it seems to make the rear shift and shimmy side-to-side.

Other than the powerbrake incident, the only other experience the car had this past weekend was it got about 300 miles on her for a little trip to south Jersey.

The car has astock G80 posi unit and has approximately 37,000 miles on it.

So, did I break something? Is it just time for a diff service with the proper GM limited slip additive?

Any input would be appreciated. My automotive weak points are diffs and auto trans', so I have no idea what could be going on here.

Thanks in Advance.

 

[theMonch]

ttt

 

[Walt Skarb]

Change the rear end fluid and make sure the gm additive is added

 

[theMonch]

Thanks, so I guess you don't think I broke anything?

What fluid should I change it with? (GM part number would be great) I couldn't find specs on weight, brand etc. anywhere. Also does anyone have a part num on the GM additive?

 

[Walt Skarb]

When the rear end clutches stick the rear of the car will hop all over the place. Replace fluid with SAE 80w-90 GL-5 and add 4 0z. bottle of GM additive 1052358 (a Must). This should solve your problem.

 

[theMonch]

When the rear end clutches stick the rear of the car will hop all over the place. Replace fluid with SAE 80w-90 GL-5 and add 4 0z. bottle of GM additive 1052358 (a Must). This should solve your problem.

Awesome. Thanks Guys.

 

[theMonch]

Resolved

OK, well after installing the TA Performance girdle (Had to do some kind of upgarde if I was getting under there) I noticed somethiong that I missed on initial inspection. The UMI tubular upper control arm on the passenger side was missing it's bushing and mounting bolt on the front mount. This is ultimately what the problem was. The rear would **** upon left turns and the wheels would rub/bind on the frame rail. This would also account for the sway when unloading the drivetrain on the highway. Well sometimes its the simplest things that you miss. I hope to be able to order just the mounting hardware and bushings and be up and running again by next week.

Thanks again for the info.