Portal Axle Powerhouse
The Jeep progression is a natural one. You start with a Jeep that is a daily driver, then you get bit by the wheeling bug after your buddies convince you to take it out on the trail. To make it more capable, you add a lift, then bigger tires, then lockers...before you know it, you have a wrinkled Jeep leaking in your driveway, and you're begging for rides from those same buddies so you don't have to drive your softly sprung, spooled Jeep to work each day.
Jack Stanko is no different. He has owned many Jeeps over the years, including a Wrangler stuffed with a Hemi, an LS1-powered Unlimited, and a Poison Spyder Customs Bruiser. The LS1 Jeep was hard to keep cool and the Bruiser wasn't street legal, so Jack knew exactly what he wanted from his next Jeep. With only 34 miles on the odometer, he delivered his '06 Unlimited to Jake Hallenbeck at Canyon Crawler Manufacturing.
Vehicle: '06 Jeep Wrangler Unlimited
Engine: 4.0L inline-six
Transmission: 42RLE four-speed automatic
Transfer Case: Advance Adapters Atlas II
Suspension: Three-links with Grand Cherokee coil springs
Axles: Unimog 404 portal axles
Wheels: 17x10 MRW Extreme Rockcrawler bead locks
Tires: 14/42-17 Super Swamper IROKs
Built For: Getting to and from the trail and big climbs in all weather conditions
Estimated Cost: $57,000
The Unimog 404 portal axles required Hallenbeck to fabricate entirely new suspensions front and rear. Triangulated three-links constructed of 2-inch, 0.325-wall DOM tubing fitted with Rubicon Express Super Flex joints locate both the front and rear axles, while stock Grand Cherokee coils and Pro Comp shocks provide gobs of suspension travel. The front suspension is located with an asymmetrical wishbone to clear the long-pinion snout and odd diff centering on the Unimog axle.
The steering is fully hydraulic with a single-ended ram. This causes some inconsistent handling on the street, but it's powerful enough to turn the 42s on the trail with one hand. The simple coil-spring configuration adds simplicity and easier packaging than a coilover setup. The upper shock hoops are mounted low to provide considerably more extension than compression, which keeps the ride height low.
There was no exotic engine used in this build, just the stock 4.0L with an Airaid intake. The engine routes power through the stock 42RLE four-speed automatic to an Advance Adapters Atlas II transfer case with a 3:1 Low range. Why not a 4.3 or 5:1 Atlas? The Unimog axles feature a combined ratio of 7.54:1. They have 3.54 gears in the differentials and 2.13:1 gear-reduction hubs. Having the reduction out at the hubs puts less stress on the drivetrain upstream because not as much torque is present until it reaches the wheels. As a bonus, the portal axles offer a whopping 19 inches of ground clearance under the centersection. The factory air-locking differentials are powered by a PowerTank and actuated with a small air ram for simplicity. Disc brakes from Exaxt were used to replace the heavy Mercedes drums and convert the bolt pattern to a standard 8-on-6 1/2, which allows for the fitment of 17x10 MRW bead-lock wheels fitted with 14/42-17 Super Swamper IROKs. High Angle Driveline worked its magic to create a front driveshaft capable of clearing the front suspension components and connect to the Unimog axle. This shaft features three 1350 double-cardan joints and a carrier bearing to help snake it around the suspension and transmission. The mog axles feature a pinion-flange conversion from Exaxt that allows standard Toyota driveshaft flanges to be used. The flanges also shorten the long-pinion snout on the Unimog axles.
The interior of the Jeep is largely stock, with the exception of the MasterCraft Baja RS seats and a 'cage. The stock rollbar was scrapped and replaced with a six-point 'cage fabricated from 1 3/4-inch, 0.120-wall DOM tubing by Canyon Crawler Manufacturing. The 'cage fits under the stock soft top and is capable of protecting the occupants should the Jeep roll over and play dead. Further tube work was performed by Canyon Crawler Manufacturing on the front bumper, front fenders, and rocker guards. The inner fenders were retained for simplicity; however, the outer fenders were replaced with tube for greater clearance and strength.
The long-pinion snout on the Unimog differentials required the wheelbase to be stretched for adequate underbody clearance, which in turn, required other modifications. The gas tank was replaced by a Gen-Right Crawler Extreme tank to accommodate the added wheelbase. The Gen-Right tank is a more elegant solution than a fuel cell, particularly because Jack wanted to keep the interior intact. The enlarged rear-fender openings were covered with custom 1/4-inch steel corners, which contribute to the portly 6,000-pound curb weight, but they also make dented sheetmetal a thing of the past.
With the 118-inch wheelbase, this Unlimited can climb vertical waterfalls that would put most Jeeps on their lids. The biggest limitation on the trail is the 92-inch width and the lack of horsepower to spin the big Swampers when necessary. Unlike his previous Bruiser, Jack has this vehicle registered and still drives it on the street to and from the trails around his Reno, Nevada, home. The soft top still fits and the heater and A/C function, making it much more comfortable than a buggy in any situation.
Jack is planning on swapping out the tires in the near future for a set of 44-inch Super Swamper TSLs. Forget about carrying a spare with either of these wheel and tire combinations. Even if you could puncture the sidewall in one of the thick bias-ply tires, you would need to bring Hulk Hogan along to change one out-each corner weighs over 200 pounds. The tall tires are a good match for the deep gears in the Unimog axles, though, and keep the rpm reasonable when the UnliMOGted sees the pavement.
The school-bus wheelbase, full-width axles, and 42-inch Swampers require different lines than the average Jeep, but they also allow this Unlimited to make huge climbs look like a Sunday drive. It seems crazy to take a brand-new Jeep and tear it apart, but when you consider the finished cost is less than that of those goofy H2s and Escalades you see all over town, it starts to make sense. Jack has done a good job of constructing a vehicle that allows him to have his cake and eat it, too. From the inside of the Jeep, it's hard to tell it apart from any other Wrangler. Then you look out the windshield and realize that you are scaling boulders and waterfalls several feet high without any drama-that's when it becomes obvious that this isn't just another Jeep Unlimited.