Hydraulic Suspension Questions

[jcantor]

For quite some time I have been wondering how well the self leveling system on my '87 560SEL was working. It gives a very firm and somewhat rough and doesn't respond as I'd expect when the car is heavily loaded (ie doesn't return the car to the unloaded height)

Today while doing several other projects under the car, I decided to test the system by disconnecting the control arm on the valve and exercise it manually to see if the car responded. Low and behold it moved up and down beautifully just as it should. This means to me that the system is able to function properly and that the nitrogen cells are probably still sealed. However, I'm still puzzled by the rough ride and lack of response when loaded.

Could the ride quality be a shock issue rather than bad nitrogen cells?

Could the lack of height response be somewhere else in the control linkage?

jlc