2004 S4 21,000 miles.
The tires are: Continental 235/40 ZR18

Maybe that's the rated lifetime it just seems a little short.

 

Depends on how hard you drive your car, what surface you drive your car..... and of course if you have a bad alignment

Some higher performance tires have lower tread ratings, but 21K is a litle premature even for any of the tires that I have tried. I found when I daily drove in a parkade it would wear one side more than the other due to the continual turns to get out of the parking lot in one direction.

 

If you've been driving hard and cornering sharp it doesn't seen short at all. If you've been driving with a baby in the car then you could argue its a little quick. But depends on your tires and overall driving habits. Use this as an excuse to go pick up a new set of Pirellis'

 

Edited, i was really drunk haha

It makes total sense to have to get new tires at 21,000 miles of wear. Driving like a grandma I'd be amazed to get that life out of any tire (I drive spirited)

 

Where are the tires worn at?

 

What does the sidewall say for tire wear? I've worn out tires in only 600mi (at the track) If they are sticky & have low treadwear, then up.
MY EVO went threw the stock tires in about 20kmi.

 

Like previously stated, poor alignment can cut down the life of you tires as well as hurting your fuel economy. 21k miles doesn't seem to bad if they are performance tires and you drive the car somewhat hard and winding roads.

 

Hell I'd be happy to have a set for 20k!