A quick flick of the throttle...
A quick flick of the throttle cleans out the Pit Bull Rocker tires during a climb up a waterfall.
In 2007, both the plan and engine changed. The JK was taken to the extreme with a new 6.1L SRT-8 Hemi mated to a 5-45RFE automatic transmission. In the process of installing the engine, Kevin designed and started production of ceramic coated headers for the swap, which negated the immediate need for suspension modification, dramatically decreased under-hood temperatures, and increased low end power. This combination resulted in roughly double the horsepower and torque of the stock engine. The guys at 4WS.com were also able to get the Hemi swap tuned and dynoed so that it would be perfect for customers upon pick up. Just having a Hemi was good enough for a while, but more drastic upgrades were still in the future.
To tolerate the power that the 6.1L Hemi put out and the heavy wheeling Kevin wanted to do, the drivetrain was upgraded. Front and rear high-pinion Dana 60s are filled with ARB Air Lockers, Superior Evolution axle shafts, Superior 5.38 ring and pinion gears, and Mile Marker locking hubs, making the axles extremely strong yet still streetable. Attached to the front axle is a steering assist ram from Howe and a custom high-steer setup to help point the big 42s in the right direction and still keep it street legal. Bolted to the pinions are 1350 CV shafts connecting to an Atlas II transfer case with 3.8 low range gears. The 3.8 ratio lets the Jeep crawl with the low end torque the engine and transmission combination turns out and still lets the Jeep get enough speed to haul through the open flats.The front Dana 60 is kept in place using a Rubicon Express long-arm kit with 12-inch-travel Rock Krawler dual rate coil-over shocks. The front control arms were adjusted out to move the front axle 1 inch forward. In the rear, Kevin adapted the Black Diamond X2 leaf springs to move the rear axle back about 3 inches. Leaf springs were used in the rear to keep the Jeep more stable on and off-road and to handle heavy loads. So far, the leafs have been tested in Moab, Hot Springs, Arkansas, and Seymour, Missouri, with results that are even better than expected. The Jeep is completely stable and predicable and doesn't sag in the rear as much as it used to when loaded down. After moving the axles, the fenders needed to be modified to fit the 42s. Xenon flares were painted and bolted on the front. Rear flares were built on extended AEV corners and the rear fenders were cut out to match the new corners and flares.
 A quality beadlock like the...  A quality beadlock like the Raceline beadlocks and a tire with strong sidewalls like Pit Bull Rocker tires are all but required to maneuver the sidehills at SMORR off-road park in Seymour, Missouri. |  Little room was left on the...  Little room was left on the front axle after mounting the steering ram to the differential cover with a skid underneath. The high steer arms were modified to move the tie rod forward away from other steering components. The Rubicon Express Dana 60 JK track bar is dropped via a Rubicon Express Extreme Duty drop bracket. Superlift sway bar disconnects were sectioned and lengthened to handle the lift provided by the Rock Krawler 5.5-inch lift coil-overs. |  The spare tire mount on the...  The spare tire mount on the M.O.R.E. tire carrier was relocated to allow use of the trailer hitch with the 42-inch Rocker mounted. A Banks 3-inch muffler is mounted in the stock location. After much trial and error this ended up being the safest location for the muffler. Superlift Select shocks by Bilstein are mounted in the rear with the Black Diamond X2 leaf springs and traction bar. |