1989 560SEL

I conducted an experiment with my self leveling system (SLS) and did not get the results I expected. I jacked the car up and placed jack stands under trailing arms. I disconected the lever between the SLS valve and the sway bar. I then moved the lever to F and revved the engine. The fluid level in the reservior bottle dropped about 3-4 inches but the rear end of the car did not raise or lower any. I measured from the rear bumper. I put the lever back to L and fluid level in the reservior went back to where it was. I bleed the system at the valve several times during and ended up replacing about a quart with new MB fluid. The first time a bleed some fluid it was a bit foamy. Subsequent bleedings the fluid looked fine (but a darker brown color than the new fluid).

The system sure seems to be working normally but why don't I see the rear end of the car go up and down? Is my experiment flawed? The car rides ok and is not sagging in the rear. If anything, it might be a little high. I replaced the accumulators about a month ago but it looked like the old accumulators where in good condidtion. On one side the rubber boot around the piston is torn in two, the other side it is only torn a little. Neither is leaking fluid. I figure that this will eventually cause a problem.

I guess I should just put a bunch of weight in the trunk to confirm if the system is working or not.
~Dave