AMG

So, it's easy to be wise after the event, but I've just Googled "E61 rear tyre wear"...

Yesterday, at motorway speeds, the car started feeling a little vague changing lanes. Moments later the 'tyre puncture' warning symbol popped up and pulled onto the shoulder to investigate. The offside rear was obviously a little low, but with runflats, no spare, no wish to spend any more time on the shoulder than strictly necessary, and a tyre compressor in the boot, I elected to carry on about 5 miles to an exit where I knew I could safely take a proper look.

A few minutes down the road, parked in a layby, I hooked up the pump to a (hot!) tyre, ran my hands round the tread (of which, I should add, there was 5-6 mm across the whole width), hung underneath to see if there was any obvious damage (none visible), and found from the gauge it was not holding any pressure. Not good. As I know of a tyre place a further mile down the road I figure I'll make my way there and get them to take a proper look.



The inner sidewall was completely detatched from the tread. You could (I did) put your hand through the gap and reach into the carcass. I was shocked that, this being my family wagon (and consequently I am extra-conscientious about routine maintenance like tyre pressures/wear) I hadn't picked up even a hint of anything amiss (and the car had been through a main dealer interim inspection a couple of months ago).

I would estimate the tyre was 98% spot on across the whole width, and the area of extreme wear limited to the narrowest margin on the transition from tread to sidewall. I am now gathering that the stock rear negative camber and stiffness of RFTs do not make happy bedfellows. Routine look around the car and periodic check of the pressures showed nothing amiss.

On the one hand I guess you could argue that RFTs are the root cause of this. On the flip side, I'd hate to think of the consequences, particularly if I'd had my family in the car, of the same total loss of pressure (in lane 3, at a speed of around 0.85 leptons) if I'd been running conventional rubber.

So, has anyone experienced the same?
Is there a precedent for deviating from the factory camber settings - if so, to what?
To what extent are the m-sport suspended cars more affected than, say, SE spec?

Just to add insult to injury, I found a huge bulge on a rear tyre a week or so prior. Of course, it wasn't the side that failed. So I am now £425 out of pocket for TWO new rears. And, yes, I'm afraid I did put the same Goodyear NCT RFTs on...

Sorry for the essay, just a little out-of-love with the car right now, reasons in another post, to follow!

pjinca

The acceptable camber in the rear is -2.0 degrees, which is quite a bit. That is within spec for BMW E60's. That said, after going through 6 sets of rear tires I decided to get a wheel alignment. In doing so I instructed the tech to REMOVE as much negative camber as possible regardless of the handling this would sacrifice. They managed to get it down to -0.8 degrees and m current set of rear tires have lasted me over a year now (not bad for 20" summer performance tires)

AMG

Thanks for this - my thinking is to do the same. I will get an independent alignment check first, but I am not prepared to throw money away on replacing tyres that are otherwise much less than halfway through their useful life.

The car is not driven hard, far from it, as I said it's the family car and gets used for daily commute (<5 miles a day) or long motorway hauls to see family.

pjinca

By your description your tires are kaput, you'll need new ones anyway. However, using my method will make the new tires last MUCH longer