it very well could be the steering box. My 190 makes the same sort of cluck backing out of the garage on to the street. Most of my front end components are fairly new ball joints, drag link, idler arm, tie rod assemblies, strut mounts, steering shock, and one side A-Fram bushings were done. The steering box has some play and may need a rebuild. Car has close to 200,000k. I suspect the steering box.

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1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T