Do a quick search. Lots of stuff have come up.
It's a general rule of thumb to avoid first MY diesels, which are the '09s because of initial issues
2011 X5 xDrive 35d Red/Black: ZCW, ZPP, ZRC, ZTP, 300, 386, 496, 4AB, 6FL, Combox, LED Coronas. 04/11 Production