yoopmqt

I screwed up a little. One rear tire got driven with very low air, and wore the sidewall some. Not too bad, but I found a used tire on ebay with roughly the same tread left for a good deal, so I swapped it out.

Here is the problem (and I really, really don't know how the hell I did this) the new one is a 285/35/18 and it should be a 285/30/18. Obviously I have to get this changed, but how crucial is it not to drive my car until I do? It's a C4, so the different diameters I'm sure are not good for the AWD.

Is that a small enough difference to not worry about for a little while? Short trips to work/store?

Hardback

I'm not a tire expert but the only driving I would do would be directly to the tire shop to buy 2 new rears. it's a 911 not a 20 year old pickup truck...

Sneaky Pete

The different tires will not rotate the same on the same axle. I would change the tires asap.

heligear

Tires with different aspect ratios will have different sidewall heights so your tires will rotate at different speeds, this will put stress on your differential and that is not a good idea, tires are cheaper! Having said that, unless you have limited slip it would be ok for you to drive to shop for tires, that sort of thing, as the open diff will compensate. Just saying you don't have tow or trailer it if you are worried about damage.

jordanturbo

QFT, it is not good for your vehicle's diff to run two different tire sizes, but since it has an open diff you dont have to worry about it exploding while driving to a shop

Pac996

Well you could circle track the car mounting the taller tire on the outside side of the turn