This 4.5" system is designed to lift your Ford Super Duty 4.5" in front to provide room for 35” tires. This system drops your stock springs 4.5", which allows for 4.5" of lift while maintaining the stock spring rate. This system comes with a 1.75" bump stop spacer (not pictured) to prevent spring fatigue during the suspension cycle. Also included in this kit is 5” rear block kit, with 17” U-bolts for a leveled stance. This system is the ideal for all Super Duties.