This week my wife hit some black ice and slid into a curb and busted a tire. Her tires have only 4400 miles on them. She took it to the mazda dealer and they replaced just the one that popped. Should I be worried about the slight difference between the tires in terms of impact on the drive train? I am thinking it won't be a problem. Opinions ... ?

 

At that low mileage it will be ok, as long as it's exactly the same tyre.

Normally you should replace all 4 tyres at the same time on a AWD.

 

I agree with the Reaper.

 

That is one month's worth of mileage for me. Don't worry about it and drive on.