Front brake pads and rotors! Interestingly, Advance Auto Parts, Auto Zone, and CarQuest(pretty much Advance) all had the rotors for the 2001 X5 with just 6 holes. The 5 bolt holes and the rotor screw. I had to go to several stores to find the rotors with the 8 holes (+2 for the locating pin things). Other than that it was suuuuper easy. Not too happy with the Advance brake pads so far though. Not enough brake bite, although they stop fine.