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2008 Jeep Wrangler JK - The Lower Forty

Posted in Project Vehicles on August 1, 2009
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Photographers: Ken Brubaker

Man, are we sick of concept cars. And we bet if you've got a pulse you are too. You see 'em at all the major auto shows with their overly Armor All'd tires and plastic seats that crack if you even look at them hard. Zero function, 100-percent fluff. Most are dreamed up by guys who wear suits to work every day and play polo on the weekends. Then public focus groups, dorky designers with pocket protectors, and Madison Avenue fashion-types shape these horror shows into something more likely found in an '80s Sylvester Stallone movie set in the year 2018 than in real life. The companies then orchestrate a gala unveil before a sea of pantywaist newspaper and men's journal photographers who slobber over them as if they held the cure to male pattern baldness. There's no heart in these window dressings. No soul. No thrill. But for the last several years Chrysler's Mopar Underground has been changing that.

What if a maverick team within a major auto manufacturer had the proverbial keys to the candy store, able to dip from a seemingly infinite pool of the hottest OE parts to build their concept vehicles? What if this group was comprised of die-hard gearheads and real automotive enthusiasts, rather than pasty-face computer design nerds afraid of the sun and any social interaction? And what if the products of their labors were real running and driving vehicles that get wheeled hard? That's right, you'd line up around the block to buy 'em if they were ever actually made available at your local dealership.

Chrysler's Mopar Underground Team, headed by Chief Designer of Jeep and Dodge Truck, Mark Allen, already has several killer concept vehicles under its belt like last year's J8 "Sarge" concept built from an Egyptian military JK and its JT Jeep JK concept pickup from the previous year. Both examples serve as proof of The Underground's connection to the enthusiast market. The nail had been hit squarely on its head. And this year the Mopar Underground hit us all over the head with its Lower Forty JK Wrangler sporting 40-inch tires, no lift, and a gnarly Hemi engine backed by a manual tranny. Sign us up.

Chassis & Driveline
Although the eye-blistering paint job is the first thing you notice when you spot Lower Forty, the second is the unbridled exhaust note from the 5.7L Hemi that the Mopar Underground team installed with components scrounged from one or another Michigan assembly plant and the help of Burnsville Off Road in Burnsville, Minnesota. The 5.7L has had the heads worked over to up the flow and the cam was swapped for one with a rowdy grind to unleash an estimated 400hp, which really makes the tires snap to life considering the aluminum-headed beast isn't mated to a power-sapping slushbox tranny.

Using more components and help from Burnsville Off Road, Lower Forty is sporting a Getrag 238 six-speed manual gearbox, which first saw action in the Chrysler lineup starting with the '05 Dodge Dakota and Dodge Ram 1500 platforms. Admittedly, it's got its work cut out for it living with all that power and big 40-inch tires, but it's sooo nice to be able to row through the gears manually we'll never complain. Backing the Getrag is a NVG241OR transfer case that's not exotic, but gets the job done.

Axle-wise, a pair of Mopar Performance J8 axles got the nod thanks to their much larger -ton truck-sized brakes and thicker axletubes. The housings were sent off to Dynatrac in Huntington Beach, California, to be set up with 5.38 gears and ARB Air Lockers front and rear. The front Dana 44 axle was cake, but since the rear J8 Dana 60 is a C-clip design, it gave the engineers at ARB nightmares trying to one-off modify a locker and cross pin that would allow the installation of the C-clips on the axleshafts without compromising strength. Dynatrac and Allen were adamant that this creation not blow a diff with some ham-fisted journalist behind the wheel and apparently the company came through with flying colors 'cause we didn't break it during our seat time.

As for all those intricate suspension modifications required to squeeze those big 40x13.50R20 Mickey Thompson Baja Claw Radial tires on 20-inch Mopar wheels under the body, there really aren't any. Aside from needing to remove the front sway bar because the tires contacted it while turning and replacing the stock shocks with better Bilstein units to cope with the heavy wheel and tire combination, the suspension is completely stock down to the factory JK-issue springs. That's not to say you'll be able to stroll down to your local dealership for the Lower Forty body kit.

Body & Interior
To quote Allen, "this is the most expensive way to put 40s on a JK." Why you may ask? The Underground team left virtually no body panel untouched when it went to town on an unsuspecting production 2-door JK. The grille has been reworked for clearance, the front fenders and hood line have been severely modified to move everything up and out of the line of fire of the big Mickeys, and the rear wheelwells, flares, and tubs have all been opened up and raised. The flares are 1-inch wider and 4 inches higher than a stock JK and the hood is molded from carbon fiber. The front bumper got the heave-ho in favor of a mean, clean unit built to squeeze between the factory tow hooks.

Otherwise, any body mods were purely aesthetical, with Allen's team of fabricators turning his swoopy conceptual drawings into reality. The windshield frame has been chopped 3 inches and laid back 10 degrees while being integrated into the cowl. The ring-rolled cage blends into the windshield frame before gracefully arcing over the doors and dropping stylishly to the rear of the tub. And as for the rest of the rear, forget looking for the ugly JK tailgate. Allen has a talent for blending old world Jeep styling cues into his designs and the CJ-esque tailgate with embossed Jeep logo is no exception. The relocated hinges and trick billet latch no doubt caused some head scratching to figure out, but the finished result inspires the drooledge.

Inside, the factory buckets are covered in Katzkin leather which is available through Mopar Performance and the mounting position has been dropped so you sit lower in relation to the chopped windshield. The end result is that the driver and windshield frame sit lower than in a stock JK. Despite the lower seating position, visibility isn't hampered and you wind up with a more secure feeling while piloting the red rocket ship. Oh, and that red. Want some? They call it Red Eye No. 3, but just ask your painter to lay some gold iridescent over a base of Viper Red and don't forget your shades. In the sunlight it pops with violent authority.

Good, Bad, & What's It For
The first time we spied Lower Forty is was from over -mile away and it stood out like Carmen Electra in a room full of nuns with facial hair and crossed eyes. The paint job is an eye catcher for sure. And there's no getting around the obscenely violent tune of the worked Hemi. It's bang-on-the-money and goes with the paint job like crank goes with insomnia. And given the snappy engine, a manual tranny is so much fun it should be a felony. The only bummer about the drivetrain is that, although the Getrag 238 shifts smoothly and smartly, you really don't want to romp on it for fear of killing it, so we did most of our off-road driving with the T-case in 4-Low to ease the strain on the little six-speed.

While 40s on a JK sporting no lift can never be a bad thing, if it were ours we think the first thing we'd do is swap the wheels for some 17-inch beadlocks and mount some non-directional 40s since Mickey Thompson doesn't make a 40-inch Claw for a 17-inch wheel. Although it was the intention, the similarity to a Hot Wheels toy is just a bit too strong for our tastes and besides, we like the added sidewall and lighter unsprung weight afforded by the smaller 17-inch wheel.

Why I Featured It
It's an obnoxiously loud and crass concept vehicle that negotiates the dunes in a huge pantomime of excessive noise and color. But it's also able to settle down and idle up a rock ledge, is tame enough to cruise down the street with one finger on the steering wheel, and stylistically exemplifies the highest level of craftsmanship and caring. The guys who built this weren't following orders from above. For the Mopar Underground guys this vehicle is a labor of love. That's a rare thing these days. I can't wait to see what they bring next year.

Hard Facts
Vehicle: '08 Jeep Wrangler JKEngine: 5.7L Hemi V-8Transmission: Getrag 238 six-speedSuspension: Stock JK, swaybar removedAxles: Mopar J8 Dana 44 (front)Mopar J8 Dana 60 (rear)Wheels: Forged Aluminum Mopar Performance 20x9Tires: 40x13.50R20 Mickey Thompson Baja ClawBuilt For: The show scene as well as wheeling!Estimated Cost: $100,000

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