The car is a Euro 1994 C180 Elegance and has done 190K kms and automatic. It makes this squeaky sound when we go over the traffic slowing road humps and I noticed it only last night. Had 4 people in the car of average 60kg weight each. I noticed some wet leaking marks on the pistons of the rear 2 shocks while the front 2 look ok. It would seem that the noise comes when the rears go over the road humps. Is it time to change the rears or all shocks? How can these be tested for sure? How long more can I go with these originals until they fail totally? Should I have them changed immediately or wait longer without damaging anything else? Thanks mates!