Fabtech's 6" 4 Link Conversion system for the Ford F450 and F550 Super Duty is built to handle the on and offroad demands of the truck enthusiast. This vehicle's suspension is more robust than the Ford F250 and F350 and therefore demands specialty parts only available from Fabtech. This system 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. Fabtech's 4 Link System has been proven in over 10 years of service in consumer, commercial and military applications. High quality components with properly design suspension geometry is the pinnacle of Super Duty suspension systems. Each Fabtech component is expertly built in house. Fabtech Heavy Duty Link Arms Dirt Logic 4.0 Resi Coilovers. Trac Bar Relocation Bracket. Sway Bar Drop Brackets. Pitman Arm. Rear Block & U-bolt Kit. Rear Dirt Logic shocks.