My car is MBZ 450 SL 1980. It is newly aligned (front wheel), wheels are newly balanced, tire pressure is checked but it still runs unstable at curbs, noticeable vibration, steering wheel not quite stable at high speed.
This is what has been done a few months ago: sub-frame was replaced, tie rods were replaced, had new front shock absorbers.
What seems to be the cause/s of the problem in steering instability?