If your vehicle is showing car wanders or requires constant steering correction to stay in lane, here are the most likely causes and the parts you'll need to fix each one.
If the wheels are not pointed perfectly straight (especially toe and caster angles), the car will naturally drift, requiring constant steering input. This frequently occurs after hitting a pothole or failing to get an alignment after replacing suspension parts.
Tie rods connect your steering rack to the wheels. When the joints wear out, they introduce 'play' or looseness, allowing the wheels to wander independently of the steering wheel.
Rubber bushings and metal ball joints hold your suspension in alignment while allowing it to move over bumps. When they deteriorate, the wheels shift dynamically while driving, causing the car to wander.
Tires with uneven wear patterns, low pressure, or aggressive tread designs can catch the grooves in the road (tramlining), pulling the car side to side.
The internal gears of the steering rack can wear down over time, creating a 'dead zone' in the center of the steering wheel where small movements do nothing, forcing you to overcorrect.
On vehicles with traditional steering boxes, worn linkage components introduce significant slop into the steering system, making it difficult to keep the vehicle tracking straight.
A failing wheel bearing allows the entire wheel and hub assembly to wobble slightly. This translates to a loose, wandering feeling at highway speeds, usually accompanied by a humming or roaring noise.