Couple of Questions...

[TXSTYLE]

My car has: S840A High Speed Synchronization
What is that/this exactly?

I also have Adaptive M Suspension
I want to confirm that this is NOT Air Suspension?

Also wondering about damaging the 'Upper Control Arm Bolt' when changing/lowering suspension. Any way to avoid this?

Thx in advance fellas!

- Marcus

[TXSTYLE]

This is what threw me from a Google search:

the Adaptive M Suspension gets maximum potential out of your car. Features include Dynamic Damper Control and air suspension at the rear axle, with a set-up designed for a particularly sporty driving response. The Adaptive M Suspension is only available as part of the M Sport package.

[TXSTYLE]

ANYBODY???

[RED_Y_]

You do have rear air suspension. There is a very long thread about suspension options as well as information about other brands. Search is your best friend
https://f15.bimmerpost.com/forums/sh...d.php?t=913797
Option S840A is basically top speed limiter increase since you have M sport wheels/tires.