The stabiliser bar, or sway bar as it is more commonly known, controls body roll during a turn. The stabiliser links are used to attach the stabiliser to the lower control arms of the vehicle. When one of these links is loose or broken, several issues can occur, including poor handling and braking, tire wear and noise.
As the vehicle turns, weight is transferred to the outside tires in the turn. To compensate for the added compression of the coil spring, the sway bar flexes. This flexing absorbs and redistributes weight more evenly and causes the vehicle to remain flat in the turn. With a loose or broken stabiliser link, the weight transfer is slowed down or lost, and the vehicle will tend to roll more in the direction of the defective link. It will feel like the vehicle is about to roll over in extreme cases.
During braking, the stabiliser acts as a spring to limit nose dive. When a loose or broken stabiliser link is present, the spring rate is changed slightly on the affected wheel, allowing suspension geometry to change. This may cause the vehicle to pull to one side or have premature wheel lock-up. This is caused by caster and camber changes in the front end alignment.
Tire Wear Problems
Tire wear problems can also be attributed to suspension and alignment geometry changes. As camber changes due to excessive compression or rebound of the coil spring, inside and outside tire wear can occur.
Noise is the most common complaint of a loose or broken stabiliser link. As the control arm moves with the forces applied to it by the road and driving condition a distinct pop can be heard. Another noise that may be caused by looseness is a groaning noise due to rust build-up in the affected joints of the link.
Several different problems can occur when a loose or broken stabiliser link is present, and, since this part is generally not serviceable, generally the only cure is to replace the part.