4.0" LJ Rubicon Long Arm Suspension SystemThe 4.0" long arm lift system is a complete replacement suspension system. It utilizes 4 link front axle mounting for a true and correct caster curve throughout the entire range of linear wheel travel. Other systems using radius arms, medium length arms called long arms and the rest can't match it's performance.For the rear axle, it gets better. Utilizing a true long arm rear 3-link, the upper triangulated bar pivots on a high-misalignment uni-ball joint. This eliminates the need for a rear axle track bar. The result, is incredible linear wheel travel and axle articulation, without the binding caused by the rear track bar.This system offers hard core rockcrawling performance from a system that rides and steers BETTER than stock. Do you drive your TJ daily? You now can without compromised handling. The perfect geometry of our rear triangulated link eliminates chassis yaw and adds to stability at freeway speeds. No other system available offers this advanced configuration.You want tough? All components in this suspension system are built for maximum off road punishment. We use 2 x .250 wall DOM tubing for our lower trailing arm assemblies for serious rock dragging, and 1/4" plate laser crafted bracketry throughout. This is a fully bolt-on system. No welding required to install.Rear CV type drive shaft required. Tailshaft transfer case conversion (SYE)required for Jeep NP231.Exhaust Modification Required.