Is it OK to replace 1 tyre

[Nontechmike]

I have had my Boxster only 4 weeks (fitted with std 18" Boxster S wheels) and already have a puncture in near side front caused by a nail. Local Porsche Centre has been able to source 1 Mitchelin and proposed fitting that to replace damaged tyre whilst leaving all other tyres OK. The fronts have about 6-7mm tread having done 10,000 miles whereas the rears are down to 3-4mm. I dont want to waste money buying tyres I dont need but will I get handling problems mixing new with part warn on the front.

I realise that these tyres are very difficult to get and Porsche may be trying to avoid having to pay towards replacing all 4 tyres if I need to go over to a complete set Bridgestones (assuming they cannot source another new Mitchelin for the front off side).

Should I insist on both tyres being replaced or just go for the one??

[White987S]

Nontechmike, I think you need to replace both tires on that axle. Having only 3-4 mm's left is not much tread. A new tire will be 10/32's. If the tires only had a few 1,000 miles, I'd replace just one tire, but you have over 10,000 miles.

If not, you could upset the PSM.

[wizard263789]

If it's the front tyre and it has 6 -7 mm of tread you should be ok with just replacing the punctured tyre.

I believe the tyre manufacturers recommendation is 2/3 of the tread left is ok to change a single tyre. New tyre is 8 - 9mm.

[White987S]

I now agree with Wizard, after re-reading everything, my mistake. Sorry. Replace just one tire.

[juniinc]

is it Michelin pilot?

1 tire should be ok. I believe u can find the same used tire on Ebay.

best to put a 6~7/32 tread left matching used tire,,,

Edited March 31, 2008 by juniinc

[Nontechmike]

Yes they are all Mitchelin Pilot Sports (N rated)

I guess I will go with just 1 new one on the front for the moment then.

Thanks for the advice.

[Loren]

Porsche says (in a TSB)...

"If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make, the same type and with the same specification code must always be used on each of the two axles. If tires are replaced on one axle only, the different tread depth from that on the other axle can cause a noticeable change in the familiar handling. This is especially the case if new tires are mounted on the rear axle. This effect decreases with increasing tire mileage.

When replacing a tire on an axle, make sure that the tread depth of the new tire does not differ from that of the other tire by more than 30%.

If a tire is damaged and it cannot be determined with absolute certainty that there is no ply damage with all of its consequences -or if the tire was thermally or mechanically overloaded due to a loss of pressure or other prior damage, we recommend replacement of the tire in question for safety reasons."

[djantlive]

if you aren't tracking your car, you can just patch the puncture tire too.