As you read, I have searched this out very thoroughly many times and I cannot seem to decide or figure out the culprit. Car rides level, SLS will lower and rise when manually actuated, thought right now I need to replace the Tie Rod that attached rear sway to SLS valve. When riding over a series of bumps, it resonates like a subwoofer at times! I have been trying to get the ride quality back since I got the car.

The rear is super soft and not very stable. Everything in the front has been replaced except springs. The only thing that has not been done in the rear is the springs and the Hydro Shocks. Which should I blame? Before I got the car, the rear was not set correctly and for some time it was lower than it should have been possibly loading the springs more than they should have been.

Very little else is left for my entire suspension system to be complete, any thoughts?

__________________
1987 300TDT - 195,000 (Original #14 head)
1993 190E 2.3 - 105,000
1981 300D - 250,000