Front driver side tire shimmying

Hello my name is Dave

If I understand correctly you replaced the lower control arm including ball joint, if so my next suspect would be a tie rod, usually an outer would cause this problem however I would also make sure your tire on that corner is in good shape as I have seen a broken belt in the tire cause a similar shake. I would start by jacking the car up on that corner and try to move the tire side to side like you are turning and see if you find any play, being aware that you can get some play from the steering column so I would recommend having someone hold the steering wheel while you do this.

Then try moving it by pushing in on the top and pulling out on the bottom, then reverse this action pulling on the top and pushing on the bottom. If you feel play only side to side only then the most likely problem would be the outer tie rod end, if you can put the car on a jack stand and put your hand on the outer tie rod while having someone rock the wheel and see if you can feel movement, if you do replace the outer tie rod, if you don't it is most likely the inner tie rod so while someone is rocking it side to side look to see if the inner part is moving when the other wheel isn't, if it is then you would need to replace the inner tie rod.

If you feel play both side to side and up and down then the most likely problem will be a hub (wheel bearing) and that would need to be replaced. If you don't find any movement then I would trade that tire for the one on the rear and see if the problem persists, if it doesn't then the tire most likely has a broken belt. Please keep us up to date on your progress and thank you for using 2CarPros!

The first test would be to swap the front and rear tires and see if you now feel the same vibration in the seat instead of the wheel. If you do then the tire is either out of balance (likely) or the tire has a fault like a broken belt or it is delaminating. Moving the tires would show if it's them or another mechanical issue.