It’s not often (or at all) that we share stuff from other magazines, but seeing that “Dirt Every Day” is a YouTube show (actually, one of the many to make the jump to Motor Trend On Demand), we felt it was sorta a gray area. Plus, this story and video are totally worth it. The idea to drive a Jeep underwater came from an old black-and-white photo from the 1950s when REO performed a test of similar design.
For “Dirt Every Day,” the idea was to replicate the result, but with slightly improved equipment. The machine in hand was a 1997 Jeep Wrangler “affectionately known as Tube Sock.” Working with Cummins, the Wrangler was fitted with the non-commercial common rail Cummins ISF2.8 diesel. Producing 266 lb-ft of torque and 160 horsepower handily bested the factory 140 lb-ft/120 hp output of the inline four-banger.
Advance Adapters pushed for a beefier NV-3500 five-speed manual and Atlas transfer case, which not only added some serious grunt to the Jeep’s drivetrain, but also eliminated the potential of an electronic failure. Although the Cummins is computer-controlled, DED went to waterproofing the intake, exhaust, fuel, and computer. Besides fabricating new motor mounts, DED used a 4.0L I-6 radiator (with no fan or intercooler, opting for a crossover pipe from the turbo to inlet), Air Lockers were fed off of a Powertank CO2 tank instead of an electric air compressor, and used pneumatic switches.
Getting the wiring waterproofed was a combination of dielectric grease on every terminal and plug, “stuffing the ECU in an ammo can upside down to form a bubble, and plenty of goop to seal around the wires entering the can.” Expanding foam and pliable undercoating were used to seal up the old gasket on the ammo can. With hopes of a successful run, their first pass resulted in nearly 50 minutes of running time beneath the lake’s surface, but fatefully lodging the Jeep’s big tires in silt. A second attempt in a concrete pond not only rendered clearer imagery, but a successful run to boot. Enjoy the video HERE: