I'm not sure why anyone is surprised here. All W210s are prone to rust, especially if they've ever been exposed to road salt. This is a manufacturing defect on MB's part which they have never owned up to. My suggestion to the OP is to replace BOTH front lower control arms and closely inspect the spring perch and the rest of the front suspension.



1996 E300D front control arm collapse | Mercedes-Benz Club of America


Lower control arm failure due to rust - MBWorld.org Forums



Lower Control Arm Cracked - Mercedes-Benz Forum

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