it depends.could be a bad tire with a broken belt or maybe even a wheel bearing.if it only shimmys when braking then thats a brake rotor
your car is probably trashy
The steering system in a 2005 Grand Prix is comprised of many different moving parts. The steering will shimmy when any of the parts begin to wear out.
The shimmy sensation in a vehicles steering wheel could be from several things , but the foremost likely reason is the camber being out of adjustment, and a simple alighnment should solve the issue promptly
If the bent rim is mounted on the front you would feel the steering wheel and front end shimmy or shake depending on the severity of the bend and speed of the vehicle. If the bent rim is mounted on the rear you would feel the vehicle shaking but not in the steering wheel.
You can tell that the rack in opinion steering is bad when there is excessive play in the steering will. You might also feel a shimmy in the steering wheel.
Your automobile may have a tire out of balance or a worn part in the front end causing this "shimmy" effect .
Your automobile may have a tire out of balance or a worn part in the front end causing this "shimmy" effect .
check brake rotors.
Tire out of balance, bent wheel, loose wheel bearing, defective tire, loose wheel lug nuts, & worn steering or suspension parts.
Alignment
Tire out of balance, low air pressure in the left front tire, wheel bent, out of alignment, or worn steering parts.
That would be the nut that holds the steering wheel to the steering shaft.