Thats some serious sag for almost no weight. The car should not sag that much even with 3 adults in the back.

Springs are most likely worn out. You will need an MB specific spring compressor to safely change them. You can get away doing it without (ONLY APPLIES TO REAR SPRINGS NOT FRONT) by removing inside lower arm bolt and lowering the control arm down slowly, but compressor is your safest option. S

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2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k