This is common on a number of models. Big, heavy GM cars from the '60s and '70s in particular had this characteristic, especially when turning sharply to one side while backing up. The two front corners of the car would bounce alternately up and down. On those car, you could reduce that wobble by lowering the caster settings on the two front wheels, but that resulted in a reduction in stability, and an increase in steering wander.
The first thing to do is check the alignment. Caster will not be adjustable, but pay attention to "total toe". If that is correct, look at "toe-out-on-turns". That is a designed-in angle set by the orientation of the steering arms coming off the spindles. They are angled in significantly relative to the center-line of the vehicle. Doing so causes the wheel turning away from the vehicle to turn sharper since it's making a tighter circle. If one of those arms is bent, that wheel will not turn the correct amount compared to the other wheel. The clue to that is that wobble you described will be different between turning left and right.
Most alignment computers can measure toe-out-on-turns. If that is within specs on both sides, chalk this up to part of the vehicle's personality.
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Wednesday, October 30th, 2019 AT 4:47 PM