Hi guys, I just uploaded a video guide for removing the air suspension air pump from the rear of my E53 X5. I have a dual-axle suspension. My pump was showing signs of failing - noise and susp. inactive lights. I purchased a new pump from Arnott Industries. This video illustrates how to remove the pump from the truck and housing.
https://www.youtube.com/watch?v=ckINpxAZj1w