Unusual tyre wear

[steve-V8s]

Fitted to the front of a 5 series estate this fairly low mileage Michelen Primacy HP has developed a very odd wear pattern. Initially I could hear a drumming noise at low speed, could see nothing wrong with the tyres and thought it may be a wheel bearing on the way out but could detect no play. A couple of thousand miles on the drumming at low speed is worse but there is no vibration or noise above 20 MPH.

Took a good look at the front tyres and one of them has a very odd wear pattern. In one area there are two of the internal blocks which have worn more than the rest. Is this a faulty tyre or something else ? Cant see it would be a damper or suspension bush problem as that would effect all of the tyre. only one of the worn blocks is in the pic, the other one is one block to the left.

[pic] [/pic]

[annodomini2]

Tyre too big for the wheel?

[stevieturbo]

the pic is far too close to see what you're trying to show ?

[steve-V8s]

stevieturbo said:

the pic is far too close to see what you're trying to show ?

OK I will take another one tomorrow. But the center block in the pic is a lot lower than the ones either side, that is what I was trying to show.

Think it is the correct size, they are the origonal rims and tyre size.

[cptsideways]

Delaminating carcass

[Ant.]

cptsideways said:

Delaminating carcass

He was only bloody asking.......

[stevieturbo]

Oh right, so the middle of the tyre is wearing more than the rest ? Why didnt you say that lol

Overinflated.

[russell_ram]

Think he's actually refering to the 'saw tooth' wear pattern on the leading/trailing edges of the tread blocks at the sidewall, you can just make it out in the picture. Actually pretty common - seems to be more apparent of tyres with very large tread blocks compared to less 'performance' oriented smaller blocked tyres. Probably somethiing to do with the stiffer construction of those type of tyres. And yes, when it's bad, it sounds like a f**ked wheel bearing.

Russ

[bertelli_1]

Loads of answers so far & not a correct one yet. That wear is usually apparent on cars with worn dampers, where the wheel 'bounces' along the road.

[Auntieroll]

bertelli_1 said:

Loads of answers so far & not a correct one yet. That wear is usually apparent on cars with worn dampers, where the wheel 'bounces' along the road.

Don't agree with this diagnosis in this case.
If there was a damper problem the wear would not occur in just one patch,the reason for this type of abnormal wear pattern is a failure of one or more of the bracing cords allowing the carcass to bulge ,(has the tyre been kerbed as this can cause this type of failure?) when delamination occurs the noise/vibration usually increases the faster you go,either way,get the tyre replaced!

[steve-V8s]

Dampers are probably past their best at 120K miles but can’t see that is the cause in this case as it is in a specific part of the tyre not all the way round. Don’t think it has been kerbed, particularly as it is on the inside edge, has certainly dropped into a fair few potholes though. Frustrating thing is in tread terms it is hardly worn and they ain’t cheap, as said will have to get another one. The noise is only evident at low speed and there is no vibration.

[chris1roll]

Is the wheel rim buckled or dented?

One of my wifes tyres had low but legal tread all round but for one place say 100 mm long on the inside edge where it was down to the cords
When I took the wheel off the alloy was dented.

Edited by chris1roll on Sunday 2nd May 21:38

[Pumaracing]

Jack the car up, set up a fixed pointer and rotate the wheel against it to see if there are any high and low spots on either the tread across its width or the inside and outside rims. Normally this will be either a tyre carcass or rim problem.

[steve-V8s]

Pumaracing said:

Jack the car up, set up a fixed pointer and rotate the wheel against it to see if there are any high and low spots on either the tread across its width or the inside and outside rims. Normally this will be either a tyre carcass or rim problem.

Yep. Inside of the rim is dented, could only really see it with the tyre off. Bit of a mystery how I dented the inside of the rim

[davepoth]

steve-V8s said:

Dampers are probably past their best at 120K miles but can’t see that is the cause in this case as it is in a specific part of the tyre not all the way round. Don’t think it has been kerbed, particularly as it is on the inside edge, has certainly dropped into a fair few potholes though. Frustrating thing is in tread terms it is hardly worn and they ain’t cheap, as said will have to get another one. The noise is only evident at low speed and there is no vibration.

It's possible. Think about it; it'd only take a bit of damage to the tyre to make it bump the damper harder each time it went round, and if the damper wasn't damping properly it may well exacerbate the problem.