Urethane and polyurethane sway bar bushings do a terrific job of stiffening up the suspension and improving cornering. However, sometimes urethane bushings make noise over bumps. Here's a way to make them quiet. Before you install bushings at the sway bar itself, wrap Teflon tape around the sway bar where the bushing goes, then, install the bushing over Teflon tape. No more chatter. Teflon tape acts as a load bearing surface for hard urethane surfaces, which helps the quiet.