pennetta

If the inside or outside of the tire wears considerably faster, then its wheel alignment. If the center wears considerably faster than the sides, then overinflated. Is both inside and outside edges wear considerably faster than the center then underinflated.

znod

Are your tires Dunlop run flats? Do they have less than 20K miles? If yes to both, then you may be able to get them replaced under warranty. What you describe is typical of the bad Dunlops. The wear you describe should not occur on any kind of tire if your alignment is AOK>
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Actually, this is a problem on E60 in general (inappropriate tread wear on the inside of the tire), but may be more defined or pronounced with certain wheel/tire configurations. This is not only a problem with Dunlop runflats.

However, donv is correct: if your tires have less than 20,000 miles and you are experiencing this type of wear and/or unacceptable ride noise, BMW dealers are instructed to replace the tires free of charge under warranty. This is ONLY for Dunlop runflat tires.
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What is it about the E60 that causes the problem? I remember reading that low inflation, but not necessarily what normally would be considered to be under inflation, might cause inside-tire wear on an E60. If not low inflation, then to what is the problem attributed, and how widespread is it? Ultimately, given what you say, I wonder if the problem actually lies with the Dunlop run flats. Is it possible that the Dunlops are just a convenient scapegoat? I guess we will find out since apparently Bridgestone run flats are on the 550is. Also, at least some seem to not be having trouble with their replacement Bridgestone run flats.
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Negative camber.
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Thanks. I suppose it could be adjusted out?
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You know, that's a good question.

Wear on inner rear tires is common with BMW OEM setups. For some reason BMW seems to dial in alot of factory negative camber. Maybe it's to please the Road&Track, Car & Driver reviewers when they take the test mules out to the slalom course?

It's a pretty simply DIY to reduce the OEM negative camber. Just adjust the pivot-centric bolt in the control arms, loosen the nuts, rotate the wheels (but be sure to first mark the original position before turning).
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Thanks. I don't know enough to do the job competently. I will ask my SA and my dealer's service manager to get ahead of possibly bad tire wear on my PS2s.

Ricracing

I'm afraid this statemants center and inside/outside wear is not the truth, the alignment is!

Modern tires are not that sensible to pressure faults.

This used to be the fact, but modern radial tires are not wear-sensitive to low and espesially not to high pressures, within reason.

znod

I'm afraid this statemants center and inside/outside wear is not the truth, the alignment is!

Modern tires are not that sensible to pressure faults.

This used to be the fact, but modern radial tires are not wear-sensitive to low and espesially not to high pressures, within reason.
[/quote]They may be somewhat sensitive to over/under. This topic came up recently, and I did a search on "tire wear" as I recall. The "experts" still mention over/under as reasons for inappropriate wear. I am not sure what the truth is, of course, having never seriously studied the issue.

pennetta

I'm afraid this statemants center and inside/outside wear is not the truth, the alignment is!

Modern tires are not that sensible to pressure faults.

This used to be the fact, but modern radial tires are not wear-sensitive to low and espesially not to high pressures, within reason.
[/quote]They may be somewhat sensitive to over/under. This topic came up recently, and I did a search on "tire wear" as I recall. The "experts" still mention over/under as reasons for inappropriate wear. I am not sure what the truth is, of course, having never seriously studied the issue.
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Air pressure is an integral part of the tires ability to handle load,heat and wear. The correct air pressure is just as important as sidewall stiffness or other physical parts of the tires construction and if you change any of those you will affect tire wear. The air pressure becomes a physical attribute of the tire construction.
As you overinflate a tire the sidewall has a stronger bond to the wheel than the center of the tire, so the center will expand first as you increase air pressure. This shifts the load more to the center and thus increases tire wear in that region. For underinflation, again the center section of tire is more flexible than the sidewall region so the center will push in first, as more air is released the sidewalls will cave as well.
Tire construction has changed over the years but they still can't alter the laws of physics.

znod

Right on!