It's 1998 E320 with new accumulators. The car IS NOT a soft ride. I'm talking about the old-fashioned bounce test one would do to test a shock absorber. Only I open the hatch and sit on the tail gate and bounce it up and down.
As long as I don't get the back end 'rocking" up and down too much the car bounces smoothly. But when I push down too hard the shocks seem to get firm all of a sudden at that spot about 2" below level. AS SOON as I reduce the amplitude of the bounce it's OK. BTW, this is with the car running.

Intruder