Steering wheel shakes violently. on 1997 Toyota Avalon

When brakes applied at high speed (55mph+) the steering wheel shakes violently. Just had rack and pinion replaced, 4 wheel alignment, steering system flushed. Work done at dealership. Is this brake related, is it normal 'traction control' feature, although it does it on dry pavement. Any ideas?

Asked by for the 1997 Toyota Avalon
Brake rotors(front) are probably warped. IF this symptom was not present prior to the rack replacement , then the front wheel lug nuts are probably unevenly & over-torqued leading to the rotors warping. Either way the fix would be to resurface(if still within limit for machining) or replaced (with new pads if existing pads are at or below 1/2 life).
1 more answer , 1 more comment
have brakes insp and ck for warpped rotors
Thanks to both of you, will have brakes checked.