Timfoilhat

I got the tread depth gauge. Just shy of 3/32 wear on other three tires.
My concern with shaving a tire down is more about it being done correctly...I don't want to have a tire that's lumpy, uneven, or hard to balance. I don't want to have tire warranty issues then because the lumpy hard to balance tire was intentionally modified from new. Just seems like fewer headaches to buy two. I'm going to keep the good tire as a spare should I get a second nail. I won't care so much about shaving that one if it's necessary at some point.

up-n-coming

Sounds like there isn't much wear on the other three if they are within 3/32'nds of a new tire. Buy one, put it on and be done.

Virginia Bill

It seems to me that you're spinning out scenarios to make yourself worry. First, the new tire will be within Audi's stated tolerance. Second, you can generally trust Tire Rack to do reliable work. Third, even if the new tire is shaved badly, fails, and the manufacturer won't honor the warranty, you'd just buy another new tire. Buying two new tires now to avoid the remote likelihood of buying a second new tire in the future makes no sense. The previous poster makes a lot more sense: "Buy one, put it on and be done."

Timfoilhat

Guilty as charged. I overanalyze problems and try to head off pitfalls and possibilities before I commit. The trade off of money now vs potential loss of time and added aggravation later in addition to potential great expense from quattro problems has me siding with money now.
I do appreciate the dialogue. It helps me make decisions.

Dan in St. Louis

3/32" of radius is 3/16" (0.1875") in diameter. Our tires are about 27" diameter so this is 0.7%. No problem.

up-n-coming

Haha, and I'm guilty of not saying this three posts ago. I just figured the calm voice of reason would prevail.

JDA_yeg

Tim, take that tin foil hat off

Timfoilhat

Well I was just about to give in and just get one tire...but the guy at the tire shop says "let's look in the manual and see what it says." So we looked in the manual. Manual says "Always change in pairs across the axle at the minimum." Just bought two... $480 installed. I'm pretty happy it's done.

Timfoilhat

one last post as follow up on the job...the tire shop filled the tires to the door sticker pressures. Those are max load pressure. I had to adjust mine to comfort pressures with a pressure gauge that has a bleeder valve once I got home. Then reset the "set" pressures in the MMI maintenance section.

niray99

I changed just one tire(because a nail went through). In my case, I asked the service advisor to select a tire from their stock which had the least difference from all the other tires. All my other tires were 8/32, the new tire is 9/32.