Ultimate Adventure 2007 Jeep JK Wrangler - 5.9L Cummins Diesel

If you've been following along then you know we are building a brand-new four-door Jeep Wrangler JK for this year's Ultimate Adventure trip. Plus you would already know that Ultimate Adventure is our weeklong off-road trip we do every year with a group of readers, advertisers, and friends. What you probably don't know is the scope of the enormous project we have taken on this year in order to build the Ultimate Jeep Wrangler.

Jeeps are easily the most prevalent off-road vehicles in the U.S., so the challenge of building one different enough from all the rest to lead our UA trip is pretty daunting. Luckily we found an awesome crew to help transform our bone-stock two-wheel-drive (yes, two-wheel-drive) '07 Wrangler Unlimited into a monster off-road machine. Our first stop was at Twisted Customs in Rapid City, South Dakota, where we had a six-point cage installed last month. Twisted Customs is one of the top shops in the nation when it comes to building rock-buggy chassis, so we're confident in the performance of the cage if we need it. After that we drove the Jeep to Missoula, Montana, where we enlisted the help of American Expedition Vehicles (AEV) for the majority of the buildup. AEV is to Jeeps what Saleen or Roush is to Mustangs and Lingenfelter or Callaway is to Corvette. The folks at AEV are some of the best in taking a showroom Wrangler and transforming it into a top-of-the-line luxury trail machine. Their specialty is swapping the late-model Dodge Hemis into Jeep TJs and JKs but they also sell bumpers, wheels, and a pickup-truck conversion kit to turn your Jeep TJ into a Jeep "Brute" pickup (you'll notice some parked in the background of the photos; they're really cool). In addition to its normal products, AEV has won a few design excellence awards from Chrysler for its amazing concept cars displayed at the annual SEMA industry trade show. As you can see, AEV is a perfect choice for our biggest Jeep build ever, but we must explain this from the start. What we asked them to do to our Jeep is above and beyond anything they offer to customers, so don't expect them to be offering a kit anytime soon to swap a Cummins diesel into a brand-new Jeep Wrangler. Yes, you read that right, we are putting a massive 5.9L Cummins diesel under the hood of our Ultimate Adventure Jeep, but doing so has opened up a can of worms like no other. In fact, we were lucky enough to come across the entire drivetrain and chassis of an '06 Dodge Mega Cab that was on its way to the crusher, so rather than dropping the Cummins into the 1/4-ton Jeep frame, we instead chopped and squeezed a shortened Dodge frame under the freshly channeled JK body. And here is the best part: As this is being written the Jeep is sitting in AEV's shop, in pieces, and there is less than a month until it makes its debut at the start of Ultimate Adventure. Situation normal; time to get back to work.

In fact a massive hole was cut in the firewall to make room for the engine, plus the entire heating and air conditioning system had to be removed, for good. Luckily Hobart is the official welder and plasma cutter of Ultimate Adventure so when the old shop plasma cutter started acting up, Hobart came through with one of its Airforce 625 plasma cutters to help in the removal of unwanted metal. The 625 can cut up to 1/2-inch steel so it should work great for everything on this job. About this time you're probably wondering why we were going through so much trouble, and actually so were we. But whenever we thought about how awesome a diesel-powered Jeep would be, not to mention one running a Cummins diesel from a 1-ton truck, we felt it was a good cause and a great project. Plus we knew you would all want to know if it could be done and we hate to disappoint.