Fabtech's 4 Link Conversion system for the Ford Super Duty has been designed to provide improved on road performance with the ability to tackle the most rugged offroad terrain. This high end system is a bolt on replacement to the factory Radius Arm suspension and comes with everything needed to convert to a 4 Link front suspension. The system will provide less caster change throughout the travel range which benefits on road driving. Offroad the 4 Link system will provide more articulation than a Radius Arm for increased terrain traversing at all speeds. Included in this system is the massive Dirt Logic 4.0 Coilover Conversion for outstanding damping capacity offroad with a quality on road ride. The Coilover bolts in place of the factory coil spring without removal of the coil spring bucket. The giant 4?? diameter aluminum remote reservoir mounts horizontally above the Coilover to allow for full compression travel with oversized tires. The Dirt Logic 4.0 Coilover is the biggest and baddest on the market for the Ford Super Duty. Fabtech's 4 Link System has been proven in over 10 years of service in military applications. High quality components with properly designed suspension geometry is the pinnacle of Super Duty suspension systems. System includes a free 5 year 60,000 mile powertrain warranty.