For this installment, readers have voiced their wishes for the all important suspension, wheel and tire components for our sweepstakes Jeep JK Unlimited. Everyone knows that a lift gives suspension travel as well as added clearance for larger diameter tires. This is important for trail use as they both increase trail capabilities, even on a great 4x4 like the Jeep. Readers selected a Rubicon Express 3.5-inch short arm Super-Flex suspension system to lift this Jeep. The kit retains all the factory suspension mounting points, includes spherical ball joint arm ends for maximum suspension articulation and will allow the use of 35-inch tires. Kits are available for both 2-door and 4-door Jeep Wrangler JKs (2007-up). The kit does not come with shocks, but buyers can select from a wide range of shock types to suite their needs and budget. For this install, Rubicon Express Mono Tube gas shocks were used. These shocks are tuned for coil spring suspensions and are ideal for use on street and trail. Note: a new driveshaft maybe required on 4-door installations and are recommended front and rear on 2-door installations.
The Rubicon Express says their 3.5-inch short arm Super-Flex suspension system will allow the use of tires up to 35-inches in diameter. Wheel recommendations are 8 or 10-inch wide with a 4.5-inch backspacing. With these specs in mind, readers were presented with appropriate options to choose from. BFGoodrich Mud-Terrain T/A KM2 tires sized 35x 12.5x 18 were chosen by the readers. Compared to prior generation BFGoodrich tires’, the T/A KM2 sidewall rubber compound is more resistant to cutting and tearing and the TriGard, 3-ply construction has cords that are up to 33% stronger.
The KMC XD Series black Rockstar wheels were the winner in the reader voting. These cast aluminum wheels have a distinctive look and a reinforcing ring built into the design.
Of course, the first step to any suspension installation is the removal of the stock components. With a short arm kit, this is a simple matter as no cutting or welding is required.
The Rubicon Express says their 3.5-inch short arm Super-Flex suspension system will allow the use of tires up to 35-inches in diameter. Wheel recommendations are 8 or 10-inch wide with a 4.5-inch backspacing. With these specs in mind, readers were presented with appropriate options to choose from. BFGoodrich Mud-Terrain T/A KM2 tires sized 35x 12.5x 18 were chosen by the readers. Compared to prior generation BFGoodrich tires’, the T/A KM2 sidewall rubber compound is more resistant to cutting and tearing and the TriGard, 3-ply construction has cords that are up to 33% stronger.
The KMC XD Series black Rockstar wheels were the winner in the reader voting. These cast aluminum wheels have a distinctive look and a reinforcing ring built into the design.
Of course, the first step to any suspension installation is the removal of the stock components. With a short arm kit, this is a simple matter as no cutting or welding is required.
 1 Up front, bump stock extensions are added to the axle housing bump stop pads. It’s as simple marking and drilling a pilot hole and then installing the extension with a self tapping screw. After tapping this hole, remove the bump stop. It is recommended that it be inserted into the spring and installed as an assembly to make installation easier. |
 2 Control arms are replaced in all corners with the Super-Flex. The joints allow maximum articulation at the frame ends yet retain a rubber bushing at the axle end; providing maximum articulation while retaining the vibration and bump dampening of the stock all-rubber setup. |
|---|---|
 3 The main lift comes from longer, tuned coils. The same arms and other components can be used with different length springs to obtain all the benefits of a Super-Flex system with different lift heights. This 3.5-inch kit is the tallest short-arm Super-Flex kit RE offers for the ’07-up JK. |
 4 The kit comes with a new front track bar. For max articulation, a heim-joint is used at the frame end. It retains a rubber bushing at the axle end to dampen vibration. A spherical ball joint is not used here due to space constraints, but the heim-joint serves the same purpose well. |
 5 All brake lines are replaced with longer DOT approved braided stainless steel lines. Important Note: for the JK, the brake lines are angled away from the caliper and each corner has a unique line that MUST be used only in its location. |
 6 Longer, RE Mono-tube gas shocks replace the factory units and are tuned for use with the coil springs. |
 7 The swaybar end links are replaced with quick disconnect units that allow for added front articulation on the trail and fast reconnect for the pavement. A parking bracket is provided to keep the bar up and out of the suspension when disconnected for the trail. |
 8 At the rear, the stock track bar is retained but a relocation bracket is used. It’s best to install the bracket with all but the last lower bolt; then the rear anti-sway bar extension and then install the last bolt in the bracket. It’s the easiest way to get everything in place. |
 9 As with the front, the rear control arms are replaced with those from the kit. These too feature Super-Flex joints at the frame end for maximum articulation. |
 10 It’s important to adjust the brakeline so that it doesn’t ride on the rear sway bar. This is a simple but often overlooked step. The rear E-brake cables must also be released from the upper body clips over the axles allowing the E-brake cables to function properly. |
 11 The BF Goodrich Mud-Terrain T/A KM2 tires were mounted to the black KMC XD Series Rockstar wheels and precision balanced. |
