Bizaar story of the day:

Last month I put on my snow tires and winter wheels. At that time I told the dealer to repair a minor scratch on the 7 month old OEM rim that happened when I was going about 1 MPH pulling straight ahead into a parking space, trying to get as close to the curb as posible to avoid being dinged by a car parking along side me.
I checked the rim and saw a minor scratch, perhaps 2 inches long and barely visible. I drove on the wheel and tire for about 2 months, figuring I would get it fixed when I put on the snow tires

After almost 4 weeks, I called the dealer to find out where the wheel was, and the body shop told me the wheel had just
come back, but there was no tire on it!

The bodyshop claims there was a large tear in the sidewall, so he just threw it away without telling me!!


After a rather verbal response on my part, I am getting a new Michelin pilot rib for my C4S


I wonder what really happened??

 

WTF!

 

How old was the tire and how many miles was on it. I'd make them get another tire for the other side because you're suppose to change tires together on the same axle. Even Porsche puts this info out and in all the manuals. You should not have to pick up the tab because of their screw up. It's a handling safety issue and bring that up repetitively so that they understand. I'd push the safety issue big time.

 

tire was only 6 months old and had 3500 miles, will this be ok?

 

If it's on the front, I think you would be OK.

 

It's an AWD car and if the PSM detects out of roundness, it will cause you headaches and some handling issues. I got a flat on my left rear and I'm changing out both tires this week. Mine only has about 6K usage and you can see the difference on the tire treads between new and old. If you can see that with the naked eye, then the car can pick it up because it's trying to roll and compensate in the variable roundness diameter of the worn tire and new tire on the same axle. In other words, the car will be in a constant state of confusion and will not be able to handle very well.

 

dealer finally admitted they threw the tire out by mistake and will buy me a second tire if the tread difference is over 30%

 

Mal - what dealer is this?

 

That sounds way too much. The criterion circumference. The diff. of the circumferences of the 2 tires has to be a fraction of an inch.

 

I got the 30% from the owners' manual

I deal with Fred Baker Porsche, in Cleveland, except for this (and I blame the body shop, not the service area) they have been great to deal with

 

If the book says 30% difference, than that should be alright. Porsche is never wrong.

 

I'm not as familiar with the the sensitivity of Porsche AWD systems, but I know in some cars (Mercedes, Subaru) the traction control is so touchy you HAVE to have all 4 the same size, or damage to the drivetrain will result. 30% sounds pretty high to me, but if Porsche says it's OK........

If the dealer won't buy you another tire to match the new one, I can shave the new tire down to the depth of the old one. Just have the tread depth measurement handy (in 32th's on an inch) when you call.

 

I just checked my other tire, it has/4 inch depth, what is the depth of a new pilot rib? thanks

 

I found it, new depth is 9.5 /32 inches, my old tire is 1/4 or 8/32 inches, a difference of less than 30%, so hopefully I'll bo ok

 

Wardhog, you are right, that small difference will mess with the awd/psm. You must change tires in pairs(at least) on a C4S.