At what point to change a tyre...

RainbowLaura

Thanks so much for the helpful responses. I think on balance I'm happy to wait, but will definitely keep an eye on it

beefturnmail

Also, bear in mind that performance in the dry actually improves the more they are worn - this is why F1 cars use slicks (i.e no tread) in the dry

EdGasketTheSecond

When its down to 1.6mm over the centre 3/4 of the tyre. Tread depth only makes a difference in wet conditions when you should allow for the weather and drive accordingly.

Joe_Horner

Wear also slows over the life of the tyre because the tread blocks move less (which is also why handling and responsiveness sharpen up), so that last couple of mm or so can represent 40% or more of the useful life.

RichardD1970

beefturnmail wrote: »

Also, bear in mind that performance in the dry actually improves the more they are worn - this is why F1 cars use slicks (i.e no tread) in the dry

Is that true of normal road tyres though?

F1 tyres are specially formulated and constructed and have to be worked quite hard to get them hot before they perform at anything like their full potential.

redux

Tarambor wrote: »

If we were coming up to winter I'd change it at 3mm. However we're not so I'd run it down more. You're only likely to get a couple of thousand miles out of it so as others have said, now is the time to start looking around.

Even then, I wouldn't necessarily call it urgent. The spare might have usable depth, and a millimetre of that can bring the current front tyres to the same wear state. I'd look to wear the right from 3 to 2 mm, then put the spare on if suitable, and eventually move both rears to front with a new pair on the back.

James2k

Carrot007 wrote: »

Best to change in pairs.

well, technically best to change in fours. especially if running 4wd/awd

Mercdriver

James2k wrote: »

well, technically best to change in fours. especially if running 4wd/awd

If you like wasting money. AWD is different to permanent 4WD. For example my CX5 has a bias towards FWD and will use rear wheels on demand. If the rear tyres don't need changing, then I wouldn't change them unless they were at similar wear to the front.

AdrianC

Mercdriver wrote: »

AWD is different to permanent 4WD.

Only on vehicles with more than four wheels.

Mercdriver

AdrianC wrote: »

Only on vehicles with more than four wheels.

My CX5 like many SUVs that are AWD only drive with all 4 wheels when the car demands it. So the wear pattern will be different.