Even though the longer wheelbase of a Wrangler Unlimited makes it a better Jeep in our minds, there is still plenty to add that the factory never thought of or just plain left off the Jeep for cost savings. Let's face it, somewhere underneath Jeep's 50-plus-year off-road-inspired heritage is a DaimlerChrysler bean counter who calculates the cost of, and subtracts, components that enthusiasts would want. That's why over the past few issues we took an '04 1/2 Jeep Wrangler Unlimited with 200 miles on it and began our project. What we wanted was a longer-wheelbase Jeep that could climb difficult trails without worrying about component failure. We didn't want a tube buggy; this Jeep had to be something that could easily hold the family and even make trips on the road to the store if need be. In addition, we wanted it to be built with nearly 100 percent bolt-on parts. We think we ended up with just about what we were looking for.
The only major mechanical changes to the Jeep are in the suspension and axles. The 4.0L engine, 42RLE four-speed automatic tranny, and NV231 transfer case are all stock, even down to the original slip-yoke rear output. As we've mentioned in other stories, the 42RLE is a pathetic transmission. It's not necessarily weak, but it does nothing to enhance the driving experience and power output of the 4.0L in any Wrangler. When creeping in the rocks in First-gear low range with 5.38 axle gears, we could actually get the Jeep into a position where it wouldn't move or spin the tires, even with the gas pedal floored. The engine simply revved up to about 2,000 rpm and the tranny and torque converter absorbed the power and probably created massive amounts of heat. Continued use like this will eventually smoke the transmission, so we highly recommend a tranny cooler if you've added larger tires to your auto-equipped Jeep. If it were available at the time, we would have preferred the NSG 370 six-speed manual tranny. We may even swap one in eventually because this automatic is a joke, at least for our application.
If all you hit is rocky terrain, then you could opt for a lower aftermarket transfer-case gearset. The Unlimited Rubicon model has a NV241 with a 4.0:1 low-range ratio, which will work great when creeping. However, to us it's not ideal when blasting through dunes or mud. We prefer the 2.72:1 ratio since the 4.0L doesn't make crazy tire-spinning power in high range. Now, if Jeep would pony up and offer a V-8 as an option in Wranglers, the 4.0:1 transfer-case low range would be perfect since we could actually use high range with the added power.
Our 37x12.50R17 BFG Krawler KX tires are really too much tire for the factory axles, especially since durability and reliability were tops on our list. We went with Dynatrac Pro Rock 60s front and rear. The lowest ratio available for the high-pinion 60 axles is 5.38:1, so that's what we installed. The ratio is about right with the overdrive on the highway. The 5.38s keep the Jeep's pathetic four-speed auto from hunting for the right gear. When we first installed the lift, our planned wheels weren't ready, so we made due with some regular 17x8s. Since then, we slapped on the polished 17x8 1/2-inch Walker Evans Racing wheels complete with extra-wide CORR-racing-type bead-lock rings. You can order the wheels with a wide variety of lug patterns, ring colors, and backspacing. We spec'd ours out with a 5-on-5 1/2 lug pattern with 4 3/4 inches of backspacing to work with our slightly wider Pro Rock axle assemblies.The BFG Krawler tires are some of the best tires we've ever used in the rocks, which is perfect since that's where this Jeep spends most of its time. The Krawler tires actually work well in any terrain, and they provide a unique, aggressive, children-eating look, even if you only plan to wear them out on the street.
Since the installation of the Rubicon Express long-arm lift kit on our Wrangler, we've made a few changes to the suspension. The original stiff front sway bar was ditched for a Currie Anti-Rock unit with aluminum arms. This helped provide a smoother ride and keeps us from going nuts when dealing with sway-bar disconnects. We like having the light sway bar for off-road use. Completely disconnecting it may provide more flex and a higher RTI ramp number, but it makes your Jeep less stable. Also new underneath are the Walker Evans Racing/Dynatrac shocks. The two companies worked together to build high-end, adjustable, Wrangler-specific shocks with remote reservoirs that bolt on to the factory Jeep shock mounts. The trick-looking high-zoot shocks help control axle movement for a smooth ride at speed or when creeping along. They should be available from Dynatrac by the time you read this.
The Awesome Unlimited is officially done; however, there are still some things we are considering for the future. Our transfer case is suspect. If we keep the auto tranny, we may need more gearing there. An Advance Adapters Atlas II with a 3.8 low range could find its way underneath. At the same time we would upgrade the driveshafts to 1350 U-joints and yokes. But we've also been kicking around the idea of doing what we think Jeep should do from the factory -- putting a 345hp Hemi V-8 under the hood. If that happens we want a six-speed manual for sure. Keep your eyes peeled.