If your vehicle is showing car pulls to one side when driving over bumps (bump steer), here are the most likely causes and the parts you'll need to fix each one.
Tie rods connect the steering rack to the wheels. When the ball-and-socket joints wear out, they develop play, allowing the wheel's toe angle to shift dynamically when the suspension travels over a bump.
Rubber control arm bushings keep the suspension arms firmly mounted to the frame. When they tear or degrade, the entire arm can shift under the force of a bump, causing the vehicle to steer itself momentarily.
Worn dampers fail to control the spring's oscillation. This causes excessive bouncing over bumps, which exaggerates the natural geometry changes of the suspension and steering linkage, leading to a pulling sensation.
Installing a lift or lowering kit changes the operating angle of the steering linkage relative to the control arms. If not corrected with proper alignment or geometry-correcting parts, normal suspension travel will force the wheels to steer over bumps.
Ball joints act as the pivot point between the suspension and the wheels. Severe wear allows the steering knuckle to shift independently of the control arms when hitting a bump, altering the steering angle.
The steering rack is mounted to the chassis with rubber bushings. If these fail, the entire steering rack can shift left or right when the suspension is jolted, causing an immediate pull to one side.