2013 tC w TRD lowering springs.
A year ago I hit a median w the front left wheel and bent the front left strut. I had it replaced and everything seemed fine w the car. A couple months later after an oil change and tire rotation I began experience a very pronounced left-right swaying motion on the freeway. It was so pronounced that all passengers heads will swap left and right back and forth. It's an oscillation that begins and intensifies. It doesn't occur on smooth roads. I recently replaced both rear shocks and the rear end definitely tightened up. And 3 days ago I had both front struts replaced thinking that maybe it was caused by one front strut being more worn than the other. Car feels much tighter now with all new suspension, however the swaying motion still occurs, although not as intense as before.
Does anyone have any idea what could be causing this. I truly can't tell whats happening. Its almost like the front of the car darts back and forth side to side. None of this happens on a nice smooth road. Its always on rough roads / freeway over 60mph +. My tech said the car aligns perfectly on the alignment.

 

Most cases its the tie rod but do a diagnostics on all steering linkage