Sorry if this is a bit of a noob question, but I just wanted to get peoples experience on replacing a single tyre vs all 4....apologies if my post is a bit long winded. I've had a bit of a look over Google etc and seen quite a mixed reaction so just wanted to ask in here

Some background. I have Michelin Pilot Sport 3s 225/45 on the stock 05 STI 17 inch rims, and my rex is my "weekend" car so doesn't see a lot of km's. I had a pretty bad puncture in one of my tyres that was ran flat for few km and it had a fair bit of wear on the sidewall of the tyre, so I decided it would be best to just replace the tyre.

After stressful few weeks at work (and my car sitting there being neglected), I finally got around to getting the tyre replaced and it was only when I brought the new tyre home that I remember that my WRX is AWD (duh) and have been told in the past that you should try to ensure that you have even wear on the tyres so you don't place the diff under unneeded stress.

My new tyre has a tread depth of 9/32" where as my other 3 tyres are still pretty "newish" and sitting at just on/below 7/32". The manual (and everyone on the Internet) recommends that for Subis your tyres be within a 2/32" tolerance to ensure that you don't damage your diff.

I feel that I could be pushing that limit, and wanted to know what others in this situation have done? My current tyres still have a decent amount of tread on them, and I have read a huge range of opinions on the net from "Your diff will explode" to "Nothing will happen you will be fine", hence my reluctance to run out and replace 3 good tyres without first consulting the collective knowledge of P-WRX. On the other hand I would hate to be destroying my diff in the process :S




tl:dr Replaced punctured tyre with exact same brand/model/size as the other 3 (good condition) but with just over 2/32" difference in tread wear...replace all 4 or she'll be right?

I had three different tread patterns for ages and after services etc there was no such problems with the diff! I now however have all the same tyres and the car feels far better...!

Mate just replace the one and if you find its not driving the way you'd expect then just replace the other 3?
If they're all the same tyre then I can't see a problem

Stick the rim with the new tyre on a mates car and get them to do an epic burnout, then refit to your car.

Problem solvered.

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Bye bye betty blue. Hello F6.

You will be fine , considering that you have fitted the same brand of tyre the roll out will be very close.

Secondly there are not a lot of dead straight roads in perth,most of the time there is always a differential in wheel speeds.

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According to Cody front mounts get the bitches!

haha thanks for the response guys...I thought I was over-reacting and stressing a little more than I need too, but wanted to double check.

New tyre is on the front?

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Race Torque Dyno 399 NM, 248Kw @ 20PSI

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Nah, new tyre is in right rear. Hasn't been driven yet though-