My B5 is a Quattro. I just recently replaced the front tires with brand new ones and left the back ones which have about 2.5k miles left on em, is this a good idea? If its damaging or anything like that I'd like to know how so. Thanks guys

 

It fine on a quattro cause the tires are all independent of each other. So no worries on tires qs long as they are all the same size.

 

It is not fine on a quattro as all the tires are not independant of each other. I believe the tread depth is supposed to be no more than 4/32nds difference or you will start to damage the differentials.

Check with the guys at tirerack (Miles I think is his name) as they answered this question for me when I was looking at new tires.

 

The overall height difference can't be more than 3% between any of the four tires, or the center diff will become unhappy. Pop off one of the new tires and one of the old ones, measure their circumference, calculate the diameter of each. If they're more than 3% apart you're going to want to buy two more tires.

 

Thanks. So bad idea then. But that one guy in here said no worries cause the wheels are independent of each other. He's wrong right?

 

Well sorta. Your car has a center Torsen diff that divides power between the front two wheels and the back two wheels. There's also a rear diff that does the same thing between the two rear wheels. He's wrong in that this allows you to run whatever size tires you want with no impact on the drive line. By running tires with drastically different overall diameters, you're going to put a lot of stress on the CV joints and differentials and something is going to break.

 

Tire Tech Information - Matching Tires on Four-Wheel Drive and All-Wheel Drive Vehicles

 

I never said it was ok to mix up tire sizes, but having new on the front and older on the rear will not make a big enough to damage anything. I have been doing so on my S4 for a few months. I would not do it to my car if I honestly thought it would mess up my trans or diffs. Also I put between 500 and a 1000 miles a week on my car driving to my job. So since I switched out the tires I have probably drove atleast 10,000 miles like this with no problems.

 

The Tirerack information shows an example of 2/32 differences and the negative effect it has. Then you get to the bottom and Audi says up to 4/32 difference is fine. I replaced the rears on my car and kept the fronts. Been that way for just over a year now. I just order two new tires to replace the fronts. Tread depth difference will be less than 1/32 of an inch. Same exact tire by the way. I would not mix and match tires brands and not sizes.

I didn't know you could shave street tires. I have shaved race tires before and regrooved truck tires. Learned something new today.

 

I always hated shaving tires. Quite a messy job. I believe you can order them from tire rack shaved to your specs for situations just like this.