Steering and Suspension: Binding
A worn or damaged strut mount will result in vibration, noise, and a binding steering condition. The rubber insulator of the mount gets dry and wears over time. The bearing wears and begins to bind. This binding is most noticeable as the steering wheel is turned. The strut mounts function is to mount the upper portion of the strut to the vehicle body. They contain an insulator and typically a bearing insert. The insulator insulates and prevents vibrations from transferring to the body. The bearing insert provides a smooth pivot point for the steering system. A faulty strut bearing will result in binding while turning the steering wheel.
Worn rack bushings will cause the vehicle to wander. This is because as the vehicle is turned or hits bumps in the road, the rack moves up and down in the rack mounts. This movement will result in changes to the vehicle's toe.
Rack and pinion gears are used on front wheel drive vehicles instead of a recirculating ball gearbox. They contain a pinion gear and a rack gear. These two gears remain in constant mesh. The gear is assisted by fluid from the power steering pump during turns. They can bind if worn or not adjusted properly.