Skyjacker Add A Leaf 1980-1998 Ford F-250 4 Wheel DriveSoftride(R) Add a leafs use only American steel and are shot peened with hard steel pellets at very high velocities. This shot peening compresses the surface of the steel thereby increasing the tensile strength of the leaf. Without this shot peening procedure, the maximum wheel travel and ride quality could not be achieved without sacrificing the life of the leaf. The Skyjacker(R) add a leafs are pre drilled for the center pin. Pin location varies