2005-2017 8.0 4-LINK SUSPENSION SYSTEM Ford Super Duty 2005-2017 Coil Spring/Radius Arm Suspension is a totally new design from the older 1999-2004 models. Full Traction has taken the new design and advanced it ever further with a system that improves the vehicle's suspension geometry even more! Our unique lift systems convert the Super Duty's 2-Link design radius arm suspension to a 4-Link front axle mounting with ICG -(instant center geometry) for a true and correct caster curve throughout the entire range of linear wheel travel. ICG reduces the total caster change throughout the suspension's movement - by over 70%! The result, is improved ;on center feel and control when driving or towing. You want tough? All components in this suspension system are built for maximum off road punishment or heavy duty commercial use. We use heavy duty rod ends and 2" diameter x .250" wall thickness DOM tubing for our lower leading control arm assemblies. This plus 1/4" plate laser crafted bracketry provide exceptional strength. This is a fully bolt-on system. No welding is required during installation. Durable Docker Gray powdercoat finish.