David has flagged it for you. The toughest part is prying open the case to get to the gear, after you have your vehicle up on a lift [or ramps, and accessed the case on a crawler] and pulled the transfer case. Good luck!

__________________
2006 X5 3.0 6-spd w/Evo UUC ssk
sport/premium pkgs
born Valentine's Day, 2006.