Just incase any of you guys havent seen this problem, I thought I'd post.
I'm on my second BMW X5 .. first was an E53 model (pre 07) and my current one is the E70 version (post 07)
I tow now and again obviously, and am always checking tyres etc as you do. Never had any problems with the E53 that I was aware of, and had it for 4 years. The E70 is just gone four and a bit, and has done 23500 miles, not massive, anyway spotted the outer edges of the front tyres wearing heavily, a while back and checked the tracking but it was fine. Checked it again yesterday in a different shop and showed infact it was toed out slightly, so the wear was a mystery. When it was up on the ramp the real shocker was the condition of the rears
.... from a visual inspection of the outside they looked fine, but thats not where they wear on this car, its the inside edges you need to look out for, due to the way the cars suspension is set up.
The rear axle wheels can be adjusted for camber and toe in on the axle subframes, and are factory set with negative camber to improve the cars road handeling performance, and there is no doubt , for a 4x4 its road grip is phenominal
.. but it comes at a price of inner shoulder wear.
I had its 4 wheel geometry checked by my local BMW stealer, who confirmed the set up was pretty much perfect
.... at a cost of £99.00 +VAT
Great .. that cost me 4 tyres today £1200, and you can expect to bin them when most of the tyres still have 4 to 5 mm of tread on them