Just found this on another forum. Someone asking a BMW tech at the X5 launch in Vancouver

Will the wheels from an E70 fit the F15?
The F15 has a different RDC (tire pressure monitor) system than the E70. As a result, BMW does not recommend using E70 wheels/tires on the F15.

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2011 X5 5.0i, Sparkling Bronze, Premium, Sport, Technology, Winter, Premium Sound, Comfort Access,Heated Rear Seats, Rear Climate, Running Boards, Smartphone/Bluetooth package, 20" wheels