I'm not too familiar with the w201 front set up, but it sounds like it could be a tie rod. Get a buddy to turn the steering wheel while you get on the ground and look at the tie rod. See if it is jarring and making the noise you describe. Then agian, I don't know if your car even has tie rods.

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2001 Dodge Ram 2500 Cummins Turbo Diesel - 4x4, auto, 3.54 gears, long bed
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'92 300D 2.5 Turbodiesel - sold
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