I picked up a 2002 Z06 at the auction last Friday. It has 90k miles on it. The first time I drove it, I noticed a characteristic that I had once in a 72 Torino. When I accelerate the car turns left. When I decelerate using engine compression, the car turns right. The previous owner of the Torino had replaced every in the front end trying to fix the problem, so I was left to look at the rear end which was essentially a four-link. I found some loose bushings in the lower rear control arms which were allowing the the rear end to be pushed around by the engine torque. Once I replaced them, the problem disappeared.

Now in searching on some corvette sites, I don't even know how to describe the problem, but I found a reference to a problem called "torque steer" which sounds like a good name for my problem. The only thing is that the solutions to torque steer were described as replacing engine and transmission mounts. At 90k, that's probably a good idea anyway, but from the way the car behaves, I expect to find some looseness some where in the rear suspension assembly. I haven't had a chance to put the car on a lift yet, so I haven't been able to look at how the rear suspension is put together.

My question is: Is this a common problem for high mileage C5 Z06's? And, is "torque steer" the term used to describe this characteristic?

 

I'll stick around for this one. I thought Torque Steer primarily applied to front wheel drive vehicles??

 

 

It certainly did with my 323 ft/lbs FWD Grand Prix GXP!

 

I have not heard of such issues, and I agree with the second post as to what they thought 'torque steer' was... I'll also be back to see more posts in this thread.

 

Well, I fixed the problem, but I'm too embarrassed to say what it was.

 

2 pounds of air in one tire?

 

Were the lug nuts tightened all the way? LOL

 

Maybe you were low on blinker fluid?

 

When you buy a car at the auction, you are always suspecting that the seller is dumping something with a big problem on you. Naturally, when I saw how this car was driving, I assumed there was something major to fix in the rear suspension, and that was why I got the car so cheap. As it turned out, the left rear tire only had 15 lbs of pressure in it. Once I aired the tire up and had it aligned, the car tracks perfectly under power. What a nice surprise!

 

Hey ... an easy fix. Before I saw your find I was going to say the rear tracking alignment is off. Guess a super low tire can give the same effect.

 

just had my first oil change in my c5 they put in six and half quarts of oil is that right? please email me. thanks

 

Great news I was thinking the problem was caused by the OEM F1 Supercars with 90 K on them or a totally worn out suspension!

Please let update us with your ongoing experiances w/ 90 K Z06. Maybe a high mileage Z06 isn't all that bad. Can I ask what you paid for it?

 

First, let me explain that were I looking for a car to drive daily, I probably would have bought a low miles car at a much higher price. But, my intention is to race this car in the SM/2 class of SCCA Solo racing. With that in mind, I have been looking for several months for a high mileage, possibly neglected C5 Z06 at a lower price. My thinking is that it would be a waste of money to buy a low miles car at higher price when I'm probably going to change almost everything out anyway.
In order to be competitive, I'll probably have to change all the suspension bushings to urethane, possibly switch the suspension to coil-overs, install racing shocks/struts, install new bearings, and a completely rebuild the engine with a longer stroke for more low end power.

As luck would have it, this car showed up in Vegas (I'm in Utah) at the final dealer auction of the year when dealers are dumping inventory and buyers are still short on cash from Christmas. I called a guy who was down there and had him check the car out. The only flaws besides the high mileage are tears in the driver seat, and a key scratch on the passenger side that looks like it will buff out. It would be nice to have a good Z06 seat, but most of the time the car will have a racing seat in it, anyway. The engine seems to be very strong. It has a K&N filter and seems quite loud, so it may have an after market exhaust system.

I paid less than 17k for the car delivered in Utah. Did I screw up?

 

Way back in the old days, we referred to this as oversteer and understeer. Recall the old Indy and Nascar races.

 

Airplanes do something similar. As you accelerate an airplane engine, it will torque to the left.

 

Sounds about right Read the owners manual....There is a lot of information in there.

 

No I think you did very well. The great thing is you can start from scratch with a lot of new parts, go with a coil over suspension if you can. SM2, so it sounds like you'll be putting a Supercharger on it!!

I run a SM2 Miata so I'm glad you're in Utah!!

 

Thats great now you can go another 90k miles.

 

I think there is a displacement limit on surpercharging. If I supercharge this one, then it will probably kick me up to a prepared class. With a smaller engine, you can go forced induction and still stay in SM2.

I've been looking at the Callaway coil over suspension. It's interesting, but I'm not sure how good it will be for autocrossing. I'd like to find someone else who is successfully using it in autocrossing.