It's been happening since 2 months already. Hard to tell what is the reason but in the last time I had left tie rod front brake pads replaced, then full alignment at the dealer. Happened both on summer 19s and winter 18 (these are only a year old), so wheel balance is unlikely. At about 140 km/h I would get quite hard vibration/shaking in the steering wheel which goes on and off fluently.
I have added 15mm spacers in the front to see if it changes and it did quite a lot, the shaking is more sever and appears at just over 100 km/h.
I have also noticed that there is a weird pattern - the steering wheel shakes for about 10s, then stops and out of a sudden the gear lever starts vibrating for a few seconds
Then it repeats. The engine mounts are new - vibra technics.
I know there was some damage to the left wheel about 2 years ago, but the car was driving perfectly fine at even higher speeds and on track so far. I know the left lower control arm and tie rod were replaced.
My plan is to replace the tension arm, do full alignment and wheel balance again and see if it helps, if not then replace the wheel bearing and maybe the spindle to have all suspension components on the left wheel new. Is there anything else I should look into?
There is no audible clunk when coming to a stop, no audible wheel bearing noise and none of the front suspension components feels loose. No wheel shake when braking or turning. At lower speeds car drives well.