Polyurethane is an ideal material for performance suspension bushings, motor and transmission mounts. Don't get us wrong, rubber suspension bushings and mounts are a proven compromise. However, additional horsepower, plus size tires, lifted truck suspension or lowered canyon carving street setups all mix with normal atmospheric conditions and undercar grit and grime to stress rubber bushings beyond design limits. Polyurethane bushings are firm enough to control movement and maintain alignment in sway bars, control arms, and other stressed suspension components without the harshness or resonance associated with solid metal suspension bushings. We believe that after experiencing the precise steering, road feedback and the added firmness PROTHANE™ polyurethane bushings offer, you'll never go back to rubber bushings.