I believe that you have to do something to the system to make sure it is not confused or hurt by adding lowering springs. I would look at the E39 touring forums becasue they have a very similiar suspension set up to the E53 X5. If you are looking at lowering springs for a X5 i mite go with a coilover option as a sencond thought therefore getting rid of the auto leveling feature all together making it much more easy to deal with. what kind of springs are you looking at getting and what year of an X5 are you looking to lower???
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