Needed to replace rear tires to get through the Summer. Front tires are fine. Will replace all 4 later.

Local tire dealer made me sign a waiver because the front tires had tread depth of 8/32" and the new rears have 11/32". Their max tolerance is 2/32" difference front to rear. They claimed that the center differential on an all-wheel drive car can be damaged by different tire size and they didn't want the responsibility. Sounds more like a ploy to sell me the front tires too. I pointed out that measuring the tread depth would tell them nothing about the rolling circumference of tires from different manufacturers. That got a blank stare from the 'technician'. He made me sign the waiver anyway.

Just for grins I calculated the difference in the rolling circumference of my tires given the 1/32" out-of-tolerance. For my 205/55-16 tires, the calculated difference is .196" per rotation. For the 78" circumference, that's a difference of .252%. Somehow I don't think Quattro will care. Perhaps I'll do an empirical measurement tomorrow to see how far off they really are.

<ul><li><a href="http://forums.audiworld.com/c6a6/msgs/35132.phtml">Clicky</a></li></ul>

"Needed to replace rear tires to get through the Summer. Front tires are fine."

At least you got a tire guy who cares. He could have just sold you two tires, watched your diff blow and then blamed you.

If you wouldn't say it to someone's face, why say it from behind a key board?

And if you don't think I'd say it to someones face, you are greatly mistaken.

Figures I'd get flack on this board because I decided to stand up for a salesman who is only looking after the health of his customer's car.

His comment was generic and you make it personal.

Front and rear end wear out differently and it is the most common thing to rotate tires...

He is not wearing to different shoes size for each end.

Nothing generic about it. Idiot tire SALESMEN, would have been generic.

I'm sure you can explaing why he can call someone an idiot and I'm the bad guy.

Look since I am part of the forum I've never seen such kind of reaction and this is why I think it is out of place.

Getting new tires for the front and rotating the others back is super common... and a lot of times the tires salesman don't leave you buy in peace and they want you to hhok you up with ratings specifications etc...

For Instance I went to buy tires for my wifes Volvo 940 Non turbo who hardly goes over 80-85 mph...

But the "Idiot" or call it whatever you like Tires sales man wanted me to buy a the factory specification for Speed ratings that goes up to 120 mph. (Twice as expensive of course) (The Car can't go that fast) Why I said Idiot too, because I went to some other place and find a salesman with common sense that respected my requirement and didn't insult my inteligence by threatening that a regular new set of tire will be a security hazzard.

E-town it is just an expression from Bob and a simple Tale... Don't take credit for your self and let's chill...

...so they have less tread depth than the new tires on the rear. The difference in rolling circumference is only 0.242%. Nowhere near the 3% claimed to damage a Torsen.

...when confronted with the real reason he should be concerned about the tire size, simply ignored all logic. I recognize that he has to follow company policy, I just fault him for believing it.

BTW, the car is new to me. The previous owner mounted dissimilar tires front and rear. The rears were cracked and unsafe. I'm not going to buy a full set right now so I'm just replacing the rears. My choice. Something wrong with that?

Notice the smiley, I wasn't really serious about the idiot thing. Seems some people can be a little sensitive on this board.

And then get a 4 wheel alignment and be enjoying it. Unless the fronts are a really nice tire, really new and you are matching them with the new rears, of course.

<img src="http://pictureposter.audiworld.com/56914/big_red_right_front.jpg" />
In October, "Manfred", the red A6, goes into storage for the Winter. These tires come off to be replaced by snows for use on the A4. Then Manfred gets new 17" wheels and tires in the Spring. There's always a story isn't there?

"(idiot audi owner)"

I have to be to own a fleet of these things. Sure keeps me occupied though. (8'D