I had the same issue. Wandering at highway speeds, especially in a wind. I just replaced all of the busings, ball joints (upper and lower) and complete tie rods (the old ones were so corroded I doubt that they would have loosened up enough for an adjustment). I cannot believe the difference it made. my '85 300d now tracks straight and true, and there is no longer a vibration in the steering wheel. I did all of the work myself, except for the alignment, and it was fairly easy. I had 340K on the original supsension components. It was the best $250.00 I have spent on the Benz. FYI.