[quattrogmbh]

Both rear tyres are showing signs of rubber fatigue on the outer edges. Tyres have always been kept at the correct pressure and have had Swisswax Tyre preserver applied on at least a monthly basis.

Anyone else seeing such signs of the rubber drying out and perishing?

[dxb335d]

Outer edges?

Ive only experianced inner edges? pics?

[jjbirch]

i had the same on the front after 16k miles i could see bits of metal on both side of the tyres, when you buy them new you would think this outer edge would have the most tread but it doesnt it has the least, people say its for handling and thats why it makes a good tyres to corner with

[oscarguitar]

I initially had outer edge wear with Non RFT PS2, but this has gone once I pumped the tyres up to the full Run Flat pressures. I noticed that the 18"s run at much lower pressures than the 19"s. Can't think why this should be since the car is the same weight but has marginally less surface area to support it, so you might imagine the pressure should be higher. I have always thought the 19s run very high pressures but I have tried lowering them and even a couple of pounds down ruins the handling. It might be worth trying adding a few pounds to see if it makes a difference. My PS2s are wearing evenly and look like they are not yet 1/2 worn with 8000+ miles covered.

[oscarguitar]

Mybe your Swisswax tyre preserver is destroying the compound, that would account for it being only the outer edge that is dryed out/perished!

[quattrogmbh]

That had crossed my mind, but then I would expect the fronts to be exhibiting the same symptom.

I'm starting the think it may well be the tyre pressure not being high enough and the ultra stiff sidewall flexing too much.

Thanks for the thoughts.

[Budgie]

All these tyres and wear patterns are poor really ...so many complaints and the connection is BMW not the tyre manufacters.

These can all be wrong with compounds so It has to be the way the car is set up.

[mistuhmao]

It might be an alignment issue. If your rear toe is too negative, the outer edge of your tires will wear faster even though your tire pressure is fine. Stop by NTB or Firestone to get it checked out for ~$70.

[SoYank]

Trouble is, there's that big body of water between here and the nearest NTB or Firestone shop and, German as it may be, the BMW doesn't come with a schnorkel.