KW will let you go pretty low with their coilovers. I have the Variant 3 installed in my truck and learned a few things by mistake on the setup. At first I set it so low that the suspension was riding on the bump stops and the truck was undriveable. It bounced around incessantly and both EDC and air suspension error codes showed up.

I readjusted to 230mm front height (10mm below minimum KW recommendation) and 63mm rear drop link (2mm below minimum). Now it rides fine, I like the looks, and no error codes have shown up.

Your truck might require a different height though. Also, if you are already at minimum height per KW instructions, try softening the rebound in the rear shocks.

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2010 X5M
2004 911 GT3 (track)
2003 M3 (sold)