Alarming Tyre Wear on Michelin Pilot 4S 35is

[baz-j]

I had my zed at the dealer today to see if the near side damper/strut could be replaced under the BMW insurance warranty as it had the dreaded slight misting of oil reported as an advisory at the last MOT. The good news is it's getting replaced under warranty and it will be done by Monday - astonished that it could be done so quickly as I only arranged the diagnostic check yesterday.

However, the vehicle check has shown up a horrific problem with one of the tyres which I'd like to get your opinions on. TBH I've had a lucky escape.

I have Michelin Pilot Sport 4S tyres (ie non-runflat) fitted to my 35is, they were bought in August 2017. They've done around 18000 miles.

The tyre wear at the MOT in August showed the n/s/r at 4.5/4.3/4.3mm and o/s/r at 4.5/4.2/4.0mm. I've driven 400 miles since August tops. The diagnostic video came back with the n/s/r at 4mm but the o/s/r was down to 1mm - illegal - on the inside rim with 4mm mid and outer rim. Also the inner rim had torn in not one but two places! See photos.

I've regularly been to the air station to keep tyre pressures in order and not had any untoward pressure readings - just top-ups. I keep the rears at 41 psi.

What could possibly cause this? I asked the BMW service guy about wheel alignment / tracking but he didn't think this was it - I'm not overly convinced. I suppose it could be a defective tyre but it doesn't add up based on 400 miles done since the last MOT.

 

[Rockhopper]

41 psi sounds alarming to me although it might be correct but it could also be why they are not wearing evenly across the width (more worn in the middle).

I run mine at 30.

Can’t explain the sudden wear increase though.

 

[Ole gits rule]

41PSi also seems high to me high, keep mine at 34 / 35

 

[flybobbie]

Looks like pot hole damage, colleagues Merc. tyre just been replaced after mot advised gash in tyre.
Sure you haven't hit pot hole hard and knocked tracking out.

 

[flybobbie]

41PSi also seems high to me high, keep mine at 34 / 35

I would barely be able to steer my 23i at those tyre pressures, car would wobble all over the place.
I get perfect wear pattern at 38 front and 40 rear. Higher than 40 rear would be very harsh ride.

 

[Ole gits rule]

41PSi also seems high to me high, keep mine at 34 / 35

I would barely be able to steer my 23i at those tyre pressures, car would wobble all over the place.
I get perfect wear pattern at 38 front and 40 rear. Higher than 40 rear would be very harsh ride.

I think 35 front and 40 rear is recommended - but I am a little lower on the rear and the car runs ok, not certain on wear as only done 3k miles since I picked the car up in Nov.

 

[mr wilks]

Looks like pot hole damage, colleagues Merc. tyre just been replaced after mot advised gash in tyre.
Sure you haven't hit pot hole hard and knocked tracking out.

Id have to agree :wink: that's not progressive wear , it looks like the tear you get when a low inflated tyre hits a bump & "tears" , similar can happen with a over inflated tyre , you've had 18k out of them , that ain't too bad in a rwd performance car .

 

[Ole gits rule]

Looks like pot hole damage, colleagues Merc. tyre just been replaced after mot advised gash in tyre.
Sure you haven't hit pot hole hard and knocked tracking out.

Id have to agree :wink: that's not progressive wear , it looks like the tear you get when a low inflated tyre hits a bump & "tears" , similar can happen with a over inflated tyre , you've had 18k out of them , that ain't too bad in a rwd performance car .

18k is good for certain, not expecting more than 12k if I am honest

 

[Zforbes]

It looks to me it's a low pressure issue also, they wear quick if you run below 20 psi for a short time.

If you are certain that low pressure hasn't caused this I WOULD NOT be looking to get the 4 wheel alignment done unless you have hit something very hard to cause movement or even a bend on your suspension arms.

That said I would still be looking to correct what had moved prior to an alignment.

First thing I'd be checking are the bushings, can't be done very easy when the car is on the road, needs to be up on a ramp and use a bar to feel any movement that shouln't be there. Any half decent mechanic with a ramp and a bar should be able to locate issues within a few minutes. If so, replace the bush and the tyre then keep an eye on it for uneven wear.

I DON'T agree with 4 wheel alignments as an initial fix, all you are doing is compensating for what is worn, it will continue to get worse cost you another tyre until you ultimately fix the root cause. When you do that the geo set up will need to be put back to where it was before the geo adjustments for had done in the first place.

FWIW I run tyre pressures advised by the manufacturer. It may seem high but wide and low profile tyres need to be run at high pressures to have the road contact the tyre was designed to take

 

[mr wilks]

FWIW I run tyre pressures advised by the manufacturer. It may seem high but wide and low profile tyres need to be run at high pressures to have the road contact the tyre was designed to take

If you owned a Audi or Porsche with similar sized & similar branded tyres you would be running significantly lower PSI than Bmw recommend on some of their cars so who's right ?
Also worth noting the Z4 G29 recommend less PSI than on E89 on similar sized rims ,
41 psi in a 255 30 19 on 9j rim no thanks

 

[baz-j]

Looks like pot hole damage, colleagues Merc. tyre just been replaced after mot advised gash in tyre.
Sure you haven't hit pot hole hard and knocked tracking out.

Pothole sounds a plausible cause putting the tracking way out - the camber is it for the rear? Don’t get why the service manager wasn’t entertaining tracking issue though as the nearside tyre is fine. He tried to suggest it could be the age of the tyre... oh that one might have been on the shelf longer than the other one!

Kwik fit have michelin 4s sport at £412 for a rear pair. I’ve read mixed views on whether they can be relied upon to get the tracking right for the zed though.

 

[baz-j]

It looks to me it's a low pressure issue also, they wear quick if you run below 20 psi for a short time.

If you are certain that low pressure hasn't caused this I WOULD NOT be looking to get the 4 wheel alignment done unless you have hit something very hard to cause movement or even a bend on your suspension arms.

That said I would still be looking to correct what had moved prior to an alignment.

First thing I'd be checking are the bushings, can't be done very easy when the car is on the road, needs to be up on a ramp and use a bar to feel any movement that shouln't be there. Any half decent mechanic with a ramp and a bar should be able to locate issues within a few minutes. If so, replace the bush and the tyre then keep an eye on it for uneven wear.

I DON'T agree with 4 wheel alignments as an initial fix, all you are doing is compensating for what is worn, it will continue to get worse cost you another tyre until you ultimately fix the root cause. When you do that the geo set up will need to be put back to where it was before the geo adjustments for had done in the first place.

FWIW I run tyre pressures advised by the manufacturer. It may seem high but wide and low profile tyres need to be run at high pressures to have the road contact the tyre was designed to take

Thanks for that, will get onto the service manager tomorrow morning and ask for the bushings to be checked.

 

[Busterboo]

Michelin Pilot 4S have the reputation for quite rapid wear. Here, they're worse than worn, they're illegal and dangerous.

Whatever the pressures, the alignment or any other factors, they shouldn't have been allowed to reach this condition. Shame on you, baz-j.

 

[Argyll Andy]

Is that tyre not losing pressure with splits like that?

How much air were you having to put in when you top it up?

Is this the same corner with the goosed shock?

When my MPS4S’s were fitted the garage put 41 in the rears, it was awful, dropped them down to 36 and a totally different handling car afterwards

 

[Ole gits rule]

The OP said the tyres were at 4mil all round at the MOT in August and he has driven 400 miles, not certain what he was supposed to do to stop that rate of wear.

I check mine once a month but drive 600 to 700 per month miles in the summer - I would not expect to go from over 4mm to 1mm in a month

 

[Ole gits rule]

Is that tyre not losing pressure with splits like that?

How much air were you having to put in when you top it up?

Is this the same corner with the goosed shock?

When my MPS4S’s were fitted the garage put 41 in the rears, it was awful, dropped them down to 36 and a totally different handling car afterwards

Yep, I am 35/36 rear and 33/34 front - 41 seems very high

 

[baz-j]

Michelin Pilot 4S have the reputation for quite rapid wear. Here, they're worse than worn, they're illegal and dangerous.

Whatever the pressures, the alignment or any other factors, they shouldn't have been allowed to reach this condition. Shame on you, baz-j.

As I said low miles done since mot when they were recorded at 4mm and no indication that there was a problem since - tyre pressures checked at local service station regularly too despite not doing the miles. Covid has meant that car has been sat on the drive going nowhere the vast majority of the time aince MOT. Yes it’s my responsibility to ensure the tyres are safe and yep they are getting replaced immediately. 3mm wear on that number of miles I have not seen before in 25 years of driving.

 

[baz-j]

Is that tyre not losing pressure with splits like that?

How much air were you having to put in when you top it up?

Is this the same corner with the goosed shock?

When my MPS4S’s were fitted the garage put 41 in the rears, it was awful, dropped them down to 36 and a totally different handling car afterwards

The last visit was a couple of psi topup. The bad shock is near side front, the bad tyre is off side rear.

 

[baz-j]

Is that tyre not losing pressure with splits like that?

How much air were you having to put in when you top it up?

Is this the same corner with the goosed shock?

When my MPS4S’s were fitted the garage put 41 in the rears, it was awful, dropped them down to 36 and a totally different handling car afterwards

The last visit was a couple of psi topup. The bad shock is near side front, the bad tyre is off side rear.

I was running my tyres on similar pressures to you but changed to be closer to the RFT pressures after a puncture on the Isle of Skye some years ago. The tyre pressure monitor came on within a minute or two of disembarking a small roll-on roll-off ferry coming back from a beautiful place called The Isle of Raasay. The puncture was fairly close to the side wall and I suspect might have happened when disembarking the ferry to do with the ramp which wasn’t exactly shallow.

 

[Zforbes]

FWIW I run tyre pressures advised by the manufacturer. It may seem high but wide and low profile tyres need to be run at high pressures to have the road contact the tyre was designed to take

If you owned a Audi or Porsche with similar sized & similar branded tyres you would be running significantly lower PSI than Bmw recommend on some of their cars so who's right ?
Also worth noting the Z4 G29 recommend less PSI than on E89 on similar sized rims ,
41 psi in a 255 30 19 on 9j rim no thanks

My mate with a 996 911 C4 runs his rears at 44 because Porsche recommend it in his owners manual

BMW have calculated what pressure your tyres run flat on the road (giving full road contact) based on diameter, width, profile and axle weight, I'm not clever enough to do the sums but I trust BMW are IMO so who am I to argue

Maybe this is due to increased sidewall rigidity of the RFT's that the car was designed for and running non RFT's should be lower maybe -

I don't understand though why people don't trust the recommendations and can only think they believe it i high compared to what you have run in other cars in the past. Running yoo low will cause increased tyre wear and less grip (due to less road contact) and so does running too high.

The difference between 38 and 41 is not significant IMO.