Get rid of your leaf springs and step up to a smooth riding, 4-link system from Kelderman Air Suspension Systems. Smooth ride, killer looks, and unmatched load- carrying capacity! Don't be the guy with a lifted truck who's tail is dragging on the ground once his toy hauler is hooked up! The 4-link will keep the bed at the same height whether you have 50 pounds in the bed or 5000 pounds! Designed for up to 40" tires.