Important note: Early build X5s may have front hubs with dowel pins that mate with matching holes on the original rotors. BMW changed the hub design to eliminate these dowel pins and new factory rotors do not have matching holes. It is standard practice by BMW mechanics to remove the hub dowel pins when installing new rotors. The Centric & StopTech rotors have dowel pins holes, but they are slightly undersized. If the rotor does not fit over the pins on your old hub, you may either remove the dowel pins or, an easier solution is to enlarge the dowel pin holes in the rotor with an electric drill.