tieppers

I just bought my friend 2015 z06 with 8000 miles on it. He purchased it about 6 months ago and sold it to me to order a zr1. When I drove it I noticed a high pitched whining noise from the rear. He thought it was from improper wear on rack and pinion in rear diff. We took it to the track a couple months later for the first time. We followed gms track prep to the letter with oil,brake and rear diff fluid changes. I bought the car a couple weeks ago and took it to my dealer in Charleston sc to see if they could diagnose the noise. They asked if it had been tracked, I was honest and said 1 time and have receipts for the fluid use for track prep. They said it the rear diff was "burned up" it wasn't covered. It was almost like they made up their mind before looking at the car. The said it was the worst looking differential they had seen and it was our fault for tracking it. I spoke to upper level gm advisor and they will not honor the warrenty. Has anyone else had this issue of a track car your not supposed to track or you lose the warrenty?

Redc8z06

That doesn't make sense I had Tadge himself tell me to my face to go race mine and have fun. As long as you didn't mod the car it should be covered. I would fight it.

https://jalopnik.com/scared-to-take-...cha-1768765826

And why would they have printed this: https://my.chevrolet.com/content/dam...tion-guide.pdf

"Please Note: The Corvette Z06, Corvette Grand Sport and Corvette Stingray with the Z51 Performance Package are the recommended models for track use."

See page 164: https://my.chevrolet.com/content/dam...s%20Manual.pdf

"Please Note: Participating in track events or other competitive driving without following the instructions provided may affect the vehicle warranty. See the warranty manual before using the vehicle for racing or other competitive driving."

silver74vette

It sounds like you need to visit another dealership or contact GM directly to handle this warranty issue. If the rear end was serviced properly there should not be a warranty rejection because of track time. Can you tell us a little more about what was damaged in the rear? Was it the E-diff section or the ring and pinion?

tieppers

tieppers

tieppers

Above are the pics of my "burned up" rear diff?

tieppers

I asked to speak to my regional rep and the service manager wouldn't get me in touch.. Im picking the car up paying $600 for labor and waiting for GM to step up. This is my 3rd vette and I cant believe this is how gm stands by their track car.

Tort

Definitely a crappy situation and I feel for ya. On one hand, I think GM should cover this but on the other hand, it's hard to really expect them to cover a car that's been taken to a track. You may have done everything by the book but it would be crazy for GM (or anyone else) to offer blanket coverage for a car that's been tracked once or 100 times. That said, I'd fight them if I was in your shoes...

silver74vette

Tracking the vehicle should not be justification for denial, modifications or improper maintenance are valid reasons. There are have been several issues documented here on Z06 diffs. Go to the GM website and start contacting people.

saleen556

Tort

Built for the track and warrantied for track use are two completely different things. Track use is absolutely a reason to deny a claim. I do hope they cover it though!

gunnyosu

Agreed, this is ridiculous to not be covered. GM needs to step up.

jvp

Unfortunately, this is due to improper break-in. Whether at the track or not, this is precisely why you take it easy on the car for its first 500 or so miles. Failure to do this will probably result in: a howling differential. Just like what you're experiencing.

This is a fault of the previous owner. But it's not something GM should be expected to cover under warranty at all. Not in the least. It's documented plainly in the owners manual that you're supposed to take it easy on the car for the first 500 miles, and don't touch a race track for the first 1500 miles!

There are reasons why those statements exist in the manual. Unfortunately, it's on you to replace the diff now that you own the car. That is the only fix for it.

Higgs Boson

if the dealer has been doing "too many" diff repairs then GM will flag them and potentially not pay them for the work, based on a per capita failure rate so the dealer may be quick to deny your claim for different circumstances than it not being coverable by GM.

GM has the last say, I agree let GM make the call or take it to another dealer.

silver74vette

If this is the result of improper break in then it will be denied. The dealerships denial based on the fact that it had been tracked is not the proper reason. Since he bought the car with 8000 miles and it had the whine when he got it, his buddy may have dodged a bullet.

Tort

Based on.....? Please show me where it says their warranty covers track use. Not arguing, I genuinely would like to know where you found this information that led you to believe track use is part of the standard warranty coverage.

AORoads

How is it known that the car was tracked before thorough break in period by the prior owner? I see no mention of it in OP's post. Did I miss it?

Not saying it's the only way to go, but the C7 owner in the thread below had his track prep work done by the dealer and his dealer went to bat for him. Long thread but you could be out big bucks if you don't prevail ($5300+ at dealer prices).

https://www.corvetteforum.com/forums...-on-a-z51.html

silver74vette

I was responding to JVP's post and said that "if" it was from improper break-in GM could not honor the warranty. Analysis of the wear marks and tolerances in the unit could provide a the data that GM would need to make that determination.

Redc8z06

There is another known issues with both Stingray's and Z06's coming from the factory with low fluid level in their differential and had to be topped off or as many of us did just drained and refilled it to the proper level. Mine was low.

Maybe yours was as well and why the noise?

You can read other corvette forums where owners heard whining noises which went away after finding the diff fluid low and topping it off.

silver74vette

Tells you in the book that came with the car. Page 165.
https://my.chevrolet.com/content/dam...s%20Manual.pdf

Participating in track events or other
competitive driving without following
the instructions provided may affect
the vehicle warranty. See the
warranty manual before using the
vehicle for racing or other
competitive driving.