With age comes experience. We’ve all heard this expression, and it hits home for anyone who has ever built multiple Jeeps. Take Dave Roberts, for example. With some of the most incredible off-road trails just outside his backyard in Broomfield, Colorado, this off-road enthusiast has spent years building four-wheel drives to get him all over the amazing state safely and reliably. From full-blown buggies to Hemi-powered JKs, he’s been fortunate to own, wheel, and build a variety of machines.
In fact, his latest ’18 Wrangler Unlimited Rubicon build is the sixth Jeep he’s built. While he entrusted the heavy-lifting portion of this JL build to the guys at Dixie 4 Wheel Drive in Moab, Utah, the lessons he learned from his previous builds gave him the knowledge he needed to get this one where he wanted right out of the gate. Given that his previous Wranglers had been equipped with V-8 power, one might assume that would have been the first upgrade. And here’s where things got interesting.
Unlike some of his previous builds that were lined with armor, aftermarket doodads, and a throaty Hemi rumble under the hood, his JL build was considerably dialed back. When asked why, Dave stated that he’s learned over the years that less can be more when it comes to the Wrangler Unlimited platform. In the past, one of his Hemi swaps was problematic (overheating and dismal fuel economy), and the more weight the Jeep had, the worse it performed. He also liked what Jeep did with the new JL platform; starting with a Rubicon with steel bumpers gave him most of what he needed straight away.
Having felt the power of a 6.4L Hemi V-8 under the hood of his previous Jeep Wrangler Unlimited JK, most would assume that the stock 3.6L Pentastar V-6 would be underwhelming. Thankfully, the new eight-speed automatic does a great job of making the 3.6L feel livelier in the JL. Couple this with the overheating issues he battled with one of his V-8 conversions, and keeping the stock engine in place simply became a no-brainer.
The big items that were carryover from his years of experience were the Dynatrac ProRock XD60 front and ProRock 80 rear axle set, along with a properly tuned long-travel suspension. Though there is a sound assortment of off-the-shelf lifts for the JL, Dave wanted something more similar to what’s found under a competition buggy. Hence the addition of aluminum links and 14-inch-travel coilovers. All of which required a full body-off install.
We were fortunate to get a first look at the Jeep, which Dave calls Stinky, to see just how well this rig could handle some red rock trails in Moab, Utah. While Dave plans on making some custom inner fenders and few minor upgrades, the JL is where he wants it to be. Given that it’s running massive 42-inch-tall BFG Krawlers, it’s safe to say that this Jeep won’t be backing down from too many Colorado trails any time soon.
Over axle and under power is a classic recipe for reliability off-road. Taking place of the stock front axle is a ProRock XD60 from Dynatrac. Fit with an ARB Air Locker, 5.38 gears, and Dynatrac’s massive 1550 U-joints, it’s unlikely Dave will find the breaking point of the ProRock, even with 42-inch-tall treads. To ensure steering on- and off-road would be a breeze, a hydraulic-assist steering system from PSC Motorsports was installed.
Since ‘crawling is what Dave does the most of in Colorado, the Jeep’s NVG241OR T-case stayed put. However, new 1350 CV driveshafts from Adams Driveshafts now spin the XD60 front and Dynatrac ProRock 80 rear. Securing the full-float rear axle is a custom double-triangulated four-link using 7075 aluminum links and flex joints from Summit Machine.
In place of the original fuel tank is a 25-gallon unit from GenRight Offroad. This resides at the back of the Jeep and has plenty of room for the full-float rear axle to be properly situated. Note that the added clearance under the axles comes not only from the high-mount control arm brackets, but from the fact that the King coilovers are placed atop the axle.
At each corner you’ll find 14-inch-travel King 3.0 internal bypass coilovers. Paired with each shock is a King 2.0 nitrogen-charged bumpstop. This setup allows the suspension plenty of flex and keeps the tires planted over some pretty serious terrain.
While swept towers in the front keep the shocks packaged neatly within the wheelwells, out back the vertically mounted coilovers required the tub and frame of the Jeep to be notched for the new towers. Though he sacrificed a modest amount of cargo room, Dave states the performance advantages and ride quality gains were well worth it.
Although 17-inch wheels continue to be the norm for those running a 40-inch-tall tire, we’re seeing many new builds move up to a 20-inch wheel for anything a bit larger. The advantage of this has to do more with sidewall stability than anything else. Dave’s JL is fit with a 42×14.50R20 BFG Krawler T/A KXs that are mounted to 20×8.5 Raceline Liberator forged beadlock wheels.
We wouldn’t classify this JL as tall, but it is a big Jeep. As such, Dave wanted a little help to make getting in and out a bit easier. Since he knew a traditional step bar wouldn’t survive off-road, he had a set of Rock Slide Engineering Step Sliders installed. With a retractable setup built in, it was a best-of-both-worlds solution.
Opting for the steel bumper group on the JL Rubicon gets you a setup with an easily convertible winch front bumper. Removing the endcaps and tossing in a Warn Zeon 10-S Platinum winch was all he needed to do to have a proper recovery setup. Though he’s skeptical of just how durable the bumper will be long term, he’s willing to give it a go until the Colorado trails say otherwise.
The interior of the Jeep is mostly stock, but that’s not to say it’s underwhelming. Being able to drive this Wrangler to and from the trail in comfort is a big deal. A sport cage will likely find its way inside soon, but there’s not much more Dave is looking to add beyond that.
At a Glance
Vehicle: ’18 Jeep Wrangler Unlimited Rubicon
Owner: David Roberts
Stomping grounds: Broomfield, Colorado
Build Time: 3 Months
Engine: 3.6L Pentastar V-6
Transfer case: NVG241OR
Low range ratio(:1): 4:0
Crawl ratio(:1): 103.9
Front axle/differential: Dynatrac ProRock XD60, 5.38 gears/ARB Air Locker
Rear axle/differential: Dynatrac ProRock 80, 5.38 gears/ARB Air Locker
Front: Custom three-link w/track bar, 14-in-travel, internal bypass King coilovers, Currie Antirock sway bar
Rear: Double-triangulated four-link, 14-in-travel, internal bypass King coilovers, Currie Antirock sway bar
Steering: PSC Motorsports hydraulic-assist
Tires: 42×14.50R20 BFG Krawler T/A KX
Wheels: 20×8.5 Raceline RT180 Liberator forged beadlock
Armor: Mopar steel bumper group, Rock Slide Engineering Step Sliders
Cool stuff: GenRight 25-gal fuel tank, Adams Driveshafts 1350 driveshafts, Warn Zeon 10-S Platinum winch, Factor 55 UltraHook