The Jeep Wrangler JK has been around since 2006 as a 2007 model year vehicle, and has vastly changed and expanded the Jeeping world on several fronts. This Jeep, with its coil-sprung, solid-axle suspension, was an evolution of the Jeep Wrangler TJ, and while the TJ is known for having a smooth ride in its own right, the JK was a definite improvement. Still, like most Jeeps, enthusiasts have been modifying JKs since their inception, and the development of new parts to modify them has been steady since 2007. One of our favorite suspension companies, Skyjacker, has kept their suspension designs particularly fresh despite the passage of all that time. As of a few years ago Skyjacker revamped most of their coil-based suspension kits, upgrading the company’s coil springs from single-rate to dual-rate (the benefits of using a dual-rate spring are multiple, and we will touch on some of those benefits later). This change isn’t all that the company has done, however. Shock technology changes rapidly in the aftermarket, and in keeping with that Skyjacker has introduced several different optional shocks for use with their suspension systems, the latest being the new ADX 2.0 Adventure Series line. We recently got a chance to upgrade a friend’s 2013 two-door JK Sport with Skyjacker’s dual-rate coil springs and a set of ADX 2.0 Adventure Series shocks. Here are the details.
What’s New About Skyjacker’s Dual-Rate Coil Springs?
Truth is, Skyjacker has had these dual-rate coil springs for the Jeep Wrangler JK for a while, and we’ve known about them but we haven’t had a chance to use them yet. Still, we love the idea of dual-rate, long-travel coils on most any 4×4 that uses coil springs. The way it works is this: The more tightly wrapped coils at the top of the spring provide the softer first rate that gives the vehicle a smooth ride over small bumps (as when on the highway), and also allow the spring to stretch when the vehicle is flexed-out or articulated, keeping the spring in the coil buckets at either end longer; once these top coils are fully compressed during a bump or a turn, the second rate comes into play in the lower, wider-spaced coils, which provides a firmer feel to help absorb larger bumps and helps to keep the vehicle in control and stable in turns. This is a nifty design that yields results on- and off-road.
What’s New About Skyjacker’s ADX 2.0 Adventure Series Shocks?
Brand-new to the market are Skyjacker’s ADX 2.0 Adventure Series shocks. Most of the details can be found here. These shocks feature an impact-extruded and CNC-machined T6061-T6 aluminum monotube body with a remotely mounted reservoir and a durable clear anodized and polished aluminum finish. The aluminum body and reservoir help to dissipate heat, which is the enemy of shocks off-road. The fully-displaced valving system is inspired by off-road racing shocks. Inside the shock reservoir, high-pressure nitrogen gas provides IFP (internal floating piston) performance. Each shock is custom valve-tuned for your specific vehicle. The end result is a shock that offers consistent control with excellent heat dissipation. The front shocks for Jeep JK wrangler also come with large rubber top bushings and easy-to-fit rubber lower bushings, as well as brackets to hold the remote reservoir. The rear shocks also install simply.
Installing the Lift Kit
We took part of a day to install Skyjacker’s 2- to 2.5-inch Dual Rate suspension with the new ADX 2.0 Adventure Series shocks on our friend Kenny Garcia’s 2013 two-door Jeep Wrangler Sport. The job is fairly simple, and basically consists of swapping in the coil springs, the new shocks, bumpstop extensions front and rear, and a bracket to level out the rear track bar after the suspension lift is added (this minimizes rear-end shimmy when going fast over large bumps). We also added a steering stabilizer to replace the factory unit. Kenny has removed the factory rear anti-sway bar and devised a nifty way to disconnect the front anti-sway bar by welding small tabs to the spring’s coil bucket. He then unbolts the anti-sway bar links, flips them, and bolts them to the tab when not in use.
Lift Kit Installation Up Front
Following the supplied instructions, we started with the front suspension by unbolting the axle end of the track bar and popping the drag link’s tie-rod end from the steering knuckle. We also pried open the metal bracket holding the factory brake line below the coil bucket. This made it possible for the brake line to be relocated, allowing more movement when the vehicle is flexed.
We tack-welded a washer onto the coil mount so we could zip-tie the brake line in place.
With the axle supported and the factory shocks and springs removed, we drilled holes and installed the front bumpstop spacers, per the instructions.
We then installed the new dual-rate Skyjacker coil springs and the new shocks.
The hole for the axle end of the track bar was a little bit enlarged from wear, so we made some tabs out of eighth-inch plate steel to weld over the front and back.
With that done we reinstalled the track bar and steering, torquing the bolts to factory specifications.
Lift Kit Installation Rear
With the front buttoned up we moved to the rear of the Jeep, where installation is similar and pretty straightforward.
Once again, support the axle and remove the springs and factory shocks. We unbolted the factory brake lines from the outside of the frame rail to allow the axle to drop enough to remove the springs without damaging the brake lines and ABS wiring.
We then installed the new springs, rear bumpstop spacer blocks, and then the new ADX 2.0 shocks.
The last step is to install the track bar bracket, which keeps the track bar level with the new added suspension lift. The bracket bolts in place, but requires drilling one hole for an additional bolt. We then added some small stitch-welds to the bracket to keep it from moving.
Since we plan on wheeling this Jeep hard off-road in the coming years we also took some 3/4 x 1/8-inch steel strap and made some drop-brackets for the brake lines. This ensures that the brake lines won’t get stressed when the Jeep is flexed off-road. It probably isn’t necessary on Jeeps that won’t be off-roaded much, but gives us a little more peace of mind when on the trail. Finally, we torqued the bolts to factory specifications and installed the tires and wheels.
Time to Go Four-Wheeling
With the new lift complete and a set of 35×12.50R17 tires installed, we headed to our local off-road area to see how the Skyjacker dual-rate coils and Skyjacker ADX 2.0 Adventure Series Shocks performed. The results were everything we could have hoped for.
The coils allow tons of flex (especially with the front anti-sway bar disconnected) and the dual-rate coils offer a smooth ride on the pavement, over a dirt road, or in a wash. The shocks also felt amazing, soaking up the washboards and whoops in the dry wash we blasted down.
Source
Skyjacker Suspension, 318.388.0816, skyjacker.com
Keyword: Skyjacker Dual-Rate Coils and ADX Adventure Series Shocks for Jeep Wrangler JK