I don't recall anyone that has done what you want to do. You may be breaking new ground. I think I would start with a call to Arnott to get their input. Most of the folks that don't like the air system go to coilovers.

If you haven't already I would get a well recommended Independent shop that specializes in BMWs to diagnose the problem if you aren't comfortable with troubleshooting the issue on your own. That has been the key for others that have posted air system problems here--- systematic troubleshooting.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas