dbf73

I just bunged up a rear tire, a Bridgestone RE050PP. It currently has a good 8/32 of tread. New ones have 10/32. Replace them both and have a spare or just the one?

eclou

I typically look on ebay for another single tire of the same tread depth

911/Q45

How old is the tire? After 2 years the old tire will have much less grip than the new, making for squirrely handling even at street speeds. Same story with replacing the rears more often than the fronts.

Bob Rouleau

Car will pull to one side under accel and decel with the difference in diameter

Mark Harris

Tirerack will shave a new one for you before shipping.

dbf73

funny you should mention that - that was what clued me in that the air pressure was down in that tire.

mkozink

I just had a similar experience. My wife's Boxster S had a flat in the rear passenger-side tire (could not repair since the tire had picked up a nail in the sidewall). While I would have preferred to replace only that tire I have gotten into the habit of replacing tires in pairs.

IMO, particularly with staggered fitments that can't be rotated front to rear or in most cases side to side, it simplifies things over the long run to replace tires in matched pairs. In addition, as others have alluded to, tread depth is probably not the best gauge (no pun intended) for tire replacement. Age, storage conditions and number of heat cycles is more telling from my perspective.