Why are you getting rid of the rear air suspension? That's one of the best features IMO, especially for towing and carrying heavy stuff. It's easy to lower the rear as well, you just need some lowering links.

I do recommend buying the subframe and rear lower ball joint tools... you'll suffer for a very long time if you don't have the correct tools.

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2003 X5 4.6 | 2000 540i Touring

Formerly owned:
2004 Range Rover | 2000 M5 | 2000 540i/6
1995 750il | 2003 Mercedes S500 | 2003 540i/6