I'm Guessing Tyres Are Not Meant to do This

[Wolfgang]

I noticed today that my front drivers side tyre has started doing this:



It is happening the whole way round the tyre, the 2nd crack from the right being the biggest.

Cracks are about 1mm deep, it is holding pressure.

The tyres are the original Michelin Pilot Primacy, manufactured 2008 with 20,000km on them.

Question is, how safe is it to drive, should I chuck the spare on straight away?


Any help is appreciated.

[dylan8]

Only one the one tyre...?

[Wolfgang]

Only one the one tyre...?

Yes, only the one. Strange I know.

All of them where manufactured C12 x 2008 so I don't think it is a replacement.

Car has recently been garaged for six weeks but I'm sure that has nothing to do with it as it would of affected more than one tyre.

[brad]

that's the same angle as what the belts run. I've never seen that all the way around a tyre before. Can you see the chords (fabric stuff)? If so, take it off immediately, if not you should be able to get by under normal driving conditions.

It's a bit late in the day but ring michelin & ask where to go to get a tech rep to look at it. If your desperate call Jax or Tyreplus at Sutho or the local Bob Jane or even Don Cornell at Bexley (he used to sell heaps of Michelin but maybe not anymore).

I'd almost guarantee you will get a pro-rata replacement of the tyre but you may have to buy a matching 2nd & keep the leftover as a spare. Keep in mind that the prorata price is usually off RRP, not street price & therefore may be stupidly expensive.

[Wolfgang]

Thanks for that Brad.

I don't think it is down to the belts but will look closer tomorrow. While I am at it I will check the others a lot closer.

Will give Michelin a ring on Monday and take it easy until I can get it looked at.

[PeDiES]

i wouldn't be too stressed about those, i see them on tyres all the time and nothing eventuates of it they are just small cracks/scratches

[Preen59]

Bert Munro ran over 200mph with worse tyres than that.

Just rub some boot polish into em.. Happy days.

[Wolfgang]

When applying tyre dressing after washing the car today I noticed the passenger side tyre is starting to do the same. I'll give Michelin a ring tomorrow and see what say.

[Diesel_vert]

Was the vehicle bought new or used?

[Wolfgang]

Was bought used through a dealer with 12,000km on it August 2010.

[Diesel_vert]

I was thinking that, between the two years when the vehicle was built and when you bought it, there may have been one or several external factors which caused this - assuming the tyres themselves are not faulty.

Hopefully, it just turns out to be superficial damage.

[Wolfgang]

Had a chat to the guys at the local Bob Jane today.

They seem to think the pressures have been a little low while the car has been driven hard allowing the sidewall to flex cuasing damage that has appeared as the tyres have started dyring out as they have gotten older.

Good thing is they are not dangerous... yet. As long as the cracks don't get any bigger they will be fine.

They recommended runnng a slightly higher pressure to reduce some stress on the sidewall under acceleration.

[brad]

how low & what pressures are they recommending?

[Wolfgang]

how low & what pressures are they recommending?

Sorry Brad, missed your post.

They didn't really say how low, but they have recommended to up the pressure to 40 psi. Sounds too high to me, the interior rattles enough already. Haha!

They said it wouldn't be worthwhile for the local Michelin Rep to have a look as the tyre would most likely need to be removed for a proper inspection which would probably make the cracks bigger.

[brad]

40psi won't hurt but it will be somewhat harsh & (as you said) will bring out the rattles & make the springs & dampers work harder. 36psi would be more pleasant.

I would ring Michelin Technical direct & send them the photos & have a friendly chat expressing your concerns. When i was at Goodyear (almost 30 years back), if a tyre came in like that it was in our interest for it not to let it fail (huge problems with SuperSteels at the time) and our tech guys wanted to examine the tyres. Depending on the customer (we had a lot of repeat purchasers / regulars in our workshop), we would either give them prorata discount (either off RRP or street price) on new tyres or even staff prices if they were struggling financially. We could do this as we were owned by Goodyear - the dealers didn't have the authority.