Sway bars are designed to reduce the amount of body roll, or lateral leaning, that occurs when a vehicle is cornering. They do this by transferring a portion of the load from one side of the suspension to the other. When a vehicle leans to one side during a turn, the sway bar twists, which applies force to the opposite suspension, helping to keep the vehicle level.
The effectiveness of a sway bar depends on its stiffness, which is determined by its material and dimensions. Stiffer sway bars reduce more body roll but can also result in a less comfortable ride over uneven road surfaces. Therefore, the material and design of the sway bar must be carefully chosen to achieve the desired balance between handling and ride comfort.