taemrey

I am buying a 2015 certified 2015 A3 Quattro 4 door sedan from a dealer (returned lease, clean) but one of the rear tires had a bubble in the wall and was replaced with a new tire. The other 3 are quite worn. I have been told by someone who drove a Quattro that if one tire is replace they should all be replaced with the same tire for optimal AWD mechanics. Please advise.

dreadlocks

All 4 tires have to be replaced at together, I couldn't even find a tire shop whom would do a single tire on an Audi.. that dealer is a shame, I'd question buying anything from them.

With AWD you have a front differential, a rear differential and a center differential.. with one tire bigger than the rest its going to but stress on the rear diff and center diff because as far as it knows your driving in a never ending circle and that rear tire is going faster than all the rest.

flynavy

the dealer (if its Audi) should know better than that. Tires must match on the axle, IOW if one is new and one is bald on either the front or rear axle, the diameter of the two different tires on that axle can damage the quattro system. If the others are bald anyway you (or they) should replace them all with the same type and size of tire.