JL Rising: A Rock Krawler Lift Helps Fit 37s on Our 2018 Wrangler

    JL Rising

    Jay KopycinskiPhotographer, Writer

    The all-new ’18 Jeep JL Wrangler was eagerly welcomed after a long run of JK Wrangler production. Among other things, on- and off-road performance has been improved and the flagship Rubicon models come from the factory with 33-inch tires.

    However, the owner of this JL Wrangler Unlimited Rubicon wanted a bit more height to improve approach and departure angles, and the ability to run 37-inch tires. Enter Rock Krawler Suspension. The company offers both 2.5- and 3.5-inch suspension systems for the new JL. Additionally, Rock Krawler offers several kit options based on the performance you desire for your Wrangler. The owner of this Wrangler opted to use the company’s 2.5-inch X Factor Mid Arm System. The kit includes beefier adjustable control arms, a new adjustable front track bar, triple-rate coil springs, sway bar disconnects, and rear track bar relocation bracket. We also installed Rock Krawler’s brand-new RRD 2.25 shocks. (See sidebar for more info.)

    The control arms and track bar come preassembled and Rock Krawler provides suggested starting lengths based on the lift kit height. We set lengths on a workbench and proceeded with the installation. The kit was installed at Done Right Diesel in the Phoenix, Arizona, area and Larry Zager was the technician that completed most of the project. It took about eight hours for Zager to perform the job using a lift, and the work only required common tools. We see little reason the Rock Krawler kit could not be installed in a home driveway over a weekend by following the detailed instructions provided.

    Read on for the highlights of the install.

    Results

    The Jeep got new wheels and rubber to take advantage of the taller height, and to further increase performance. It now turns 37x13.50R20LT Nitto Ridge Grapplers mounted on one-piece 20x10 Fuel Coupler wheels.

    Driving tests showed the street ride was smooth; the multi-rate coils soaked up the small pavement bumps well, and then allowed the Jeep to corner without excessive body roll as the spring rate advanced under compression. Off-road, the ride was also well behaved with the coils soaking up bumpy dirt trails effectively while providing supple flex when needed.

    With the added lift and new tires, the approach angle of the Jeep increased impressively by about 12 degrees, while the departure angle increased by 7 degrees. It was a noticeable improvement off-road. Ground clearance went up by approximately 2 inches due to the larger-diameter tires. The stance of the Jeep remains reasonably low and very stable. The kit comes with multiple bumpstop pads that can be stacked as needed. We installed the recommended two pads up front and a single pad in the rear. At full flex, we found very minor tire rubbing on some of the plastic inner fender panels and on the trailing edge of the stock front bumper, but we opted not to add additional bumpstop pads.

    About the New RRD 2.25 Shock

    We paired the 2.5-inch X Factor Mid Arm System with Rock Krawler’s hot new RRD 2.25-inch shock. Some of its features include a fluted-aluminum body that not only makes the shock lightweight, but also improves vital cooling with its increased outer surface area. The body is hard-anodized to prevent corrosion. A heavy-duty 3/4-inch Nitrotec steel shaft is supported internally with a pair of high-quality DU bearings, and then sealed up with Viton O-rings and double-lip Buna-N shaft seals to keep shock fluid in and external contaminants out. A billet aluminum–valve circuit with digressive valving controls the damping of each shock, which comes tuned specifically for the lift kit application. The RRD emulsion shocks are also fully serviceable and can be re-valved as needed.
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