Bushes connect the many different moving parts in your suspension (within your car's chassis). Old or worn bushes can reduce your car’s handling ability. As a result, it is important to replace them from time to time. This is especially true if you own a high-performance vehicle, or you want to upgrade your existing suspension. This is because performance vehicles are capable of higher speeds and require pinpoint handling. Performance bushes are made of either nylon or polyurethane and replace the soft rubber examples on many all-purpose vehicles. These high-end products reduce play between all the different parts of your suspension – thus reducing wear and tea.