I know some equate this as a front drive only problem but what I'm experiencing is similar only of course from the rear wheels. I find that when I get on it in second or third the car wants to pull to the left.

I've posted this complaint previously and one reply suggested it was over steer. Not so as I'm pointed dead straight and not cornering at this point.

The car is a very low mileage 03 Z06.

I'm wondering if I have an alignment issue or a problem with the shocks. Obviously when I accelerate hard weight transfer is occurring and if the weight transfers unevenly because of a shock issue that might be the problem.

The other thought I had was a possible problem with the limited slip differential.

Thoughts or opinions?

 

I'd get the alignment checked ... I had the same problem, rear alignment was out, and it fixed it. Good luck!!

 

Have you had a good 4 wheel alignment recently? This would be one of the first things to check.
Next thing is to check break away torque on the rear axle this will require a rather large dial tq. wrench, raise one wheel at a time and apply tq until the diff clutch slips and record the number then do the same to the other wheel.
Your numbers should be relatively close, shocks should not cause any issue since you have a torque tube.
The only other question is does this happen on a perfectly level surface?
Any road crown or slope at all will cause this if the tires is breaking traction!

 

I agree--check the rear end alignment---next i would check the rear diff--It could be slipping--Change the rear diff fluid and make sure to add the posi additive----Only other thing would be to check the rear sway bar--- the bushings and the end links---Stock bushings are rubber--replace them with poly---and if your end links are plastic--replace them with the new metal ones--( you should have metal already if so check them for wear or slop---)

 

This is almost always something loose or worn in the rear suspension and IT DOESN'T TAKE MUCH ! Be sure to ck. end links and A-arm bushings first ...

 

The first thing that I would check would be the condition of the rear trailing arm and strut rod bushings. Make sure that there is not excessevely worn OR deflect easily. Try using a pry bar and pry the wheel rearward and see if there excessive deflection.

Bad bushings would effect you alignment under heavy load.

NEXT! This happened to me and it's pretty common. Just ask RPM Transmission!

The clutch Beleview Spring could be broken and that will allow the clutches under that spring to be loose and NOT allow that wheel to propell the car forward evenly.

I did a burn out and heres what leed me to suspect a bad clutch or spring:



Compare the Right and Left mark. The right mark has a skip to it.. The right wheel also gave up before the left wheel. The right side had the broken spring.

Heres the broken spring compared to the NON Broken Spring:





Jack the rear of the car up so the tires are off the ground. Put the trans in nuteral. Have someone hold one tire/wheel while you attampt to rotate the other wheel. Make sure the E brake is OFF. There should be about 70 ft /lbs of resistance.

Compare that to the other wheel. They should be very equal to each other what ever reading you get. If one is really easy to turn,,, that means the clutches are very worn and that may be part of your issue!

Let me know what you find!

Bill

 

How old are the tires? not how many miles on them but the age?

 

3 Month old TOYO Proxis T1r tires

 

Car has less then 7500 miles on it. I had a thorough look at it last Friday when it was on a lift. Couldn't see any issues, looked, well like new!

352HP and 348 on the Dyno bone stock. Engine seems to be healthy as well.

I'm an electrical guy so my knowledge of lubricants is cursory at best. So I was wondering if the additive for the limited slip can deteriorate just by oxidization over time?

Alignment seems to me like a possible cause. I expect it's never had one.

 

Can you break the spring by doing a burn out?

The tires are original but the car was always stored indoors and at the end of the day they would have aged evenly so I'm doubtful it's rubber related.

I think I'll start with a fluid flush and fill and an alignment, after I try the break away torque test mentioned by Bill and Bob.

How easy was it to turn the wheel with the broken spring?

 

i would start by changing the diff fluid. even if it has low miles, the fluid can still break down and become contaminated causing the limited slip clutches to not perform their job very well. If it still has the original fluid, change it like yesterday.

Another possibility is that the diff fluid was changed, and the limited slip additive was not added in the correct amount, or not added at all.

If changing the fluid does not work, and the alignment doesn't work, you can count on getting your diff rebuilt.

i would suggest using the GM LS gear oil with the limited slip already added. its super expensive for gear lube, but pretty much the best stuff u can get.

edit: just saw you still have the original tires. go buy new ones immediately. You do need new tires, but I do not see this as a possible cause for consistently biasing one side. If the amount of tread is the same, and the tires are the same age, the same amount of friction is applied to each side.

 

8-9 year old tires. get some tires and an alignment. All will be well I am sure.