Hello...Please offer some helpful advise. I have a 93 500SEL .apprx 130k

Trouble is I hear a sqeaking noise from the left rear side . The cars ride is fine, but when city driving the noise is quite prominent. On the expressway the noise is a lot less, unless I hit a pretty good bump. Would this be considered a spring or shock problem? Also when I push down on then left rear side I can duplicate the trouble everytime but I don't have enough experience to tell where the noise is coming from . Thanks for any help

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