Part 4: Long-Arm Suspension System
We were in the early planning stages of Project 'Con Artist, when we contacted the crew over at Rubicon Express to see if they would be interested in putting a long-arm system on our JK. After all, we have always been impressed with the quality and performance of Rubicon's system on the TJ and they were the original innovator of Jeep long-arm suspension systems back in 1998. Two years before that, in 1996, Rubicon Express was formed and has built up a solid reputation of being one of the premier players in Jeep suspensions.
When Rubicon's JK Long Arm system was released, it quickly became one of the most controversial suspension systems on the market, utilizing a radius-arm design on the front (similar to the TJ) and on the rear, something that has been done on great factory four-wheel-drive vehicles such as the Range Rover, but never tried in the aftermarket. We heard all types of comments, from editors to armchair enthusiasts telling us why radius arms would never work off road, but none of them having real radius-arm experience to back up their claims. We decided to forge ahead and test the myths about radius arms.
We wanted a long-arm suspension for the advantage they hold over short arms, such as a shallower control-arm angle over the range of suspension travel, as well as the angle being closer to stock at an increased ride height, resulting in reduced squat. Radius arms have the added benefit of keeping the wheels from moving toward the center of the vehicle during droop and being self-canceling for torque, nearly eliminating troublesome axle hop on loose surfaces. They also result in more stable handling, because as the body rolls, the wheelbase increases on the outside of the turn and eliminates the front-end lift under hard acceleration.
Another plus is that Rubicon Express goes the extra distance in quality of materials, using chromoly for the arms, which is formed in a 100-ton press, not shaped in a bender, preserving material strength. They also specify rigorous criteria for quality of components, such as the consistency of the rubber in the bushings.
A competent shop should be able to complete the install over the course of a full day. Follow along as we point out some of the highlights of this suspension system and installation done at Rubicon Express' facility in Rancho Cordova, California.