Military trucks have always been a big part of BJ Kohlleppel’s automotive life. His collection over the years has included three M35A2 6x6s, several M998 Humvees, an M1028 CUCV, and other military iron. Among them all, the M715 has remained his favorite. That passion ultimately led him to this 1967 Kaiser M715, which he purchased in non-running condition in 2012.
Three 6.5-Liter Engines To Make One
BJ transformed the truck into a highly capable machine that serves as both an off-grid adventure rig and a dependable tow vehicle. At the heart of the build is an Optimizer 6500 6.5-liter V8 diesel assembled from components sourced from three different engines. One of those donor engines came from a friend who was converting a Humvee to a 5.3-liter gasoline V8.
To improve performance, BJ equipped the diesel with a DB2-4911 injection pump and an HX40 turbocharger. Supporting upgrades include an LB7 Duramax radiator, dual 16-inch Spal brushless cooling fans, and a Derale remote oil cooler with its own dedicated fan.
“My engine choice seems to bring out the hate,” BJ says. Despite the criticism, he reports excellent reliability from what many dismiss as the “gutless old GM diesels.”
Behind the turbocharged 6.5 sits a GM NV4500 five-speed manual transmission sourced from BJ’s parts collection. Power then flows through a Ford NP205 transfer case fitted with a GM 32-spline input. He acquired the transfer case through a trade involving a TH400 automatic transmission.
Heavy-Duty Drivetrain Built To Work
A military-inspired truck deserves a stout drivetrain, and BJ delivered.
Up front is a 2005 Ford Super Duty Dana 60 sourced from LKQ. The axle features a Yukon Gear & Axle Grizzly Locker and manual locking hubs. Steering duties are enhanced with a Redneck Ram hydro-assist system.
The rear axle is a GM 14-bolt removed from a 2002 Chevy 2500 donor truck. It features disc brakes and an Eaton Detroit Locker. Both axles are geared with 4.56:1 ring-and-pinion sets.
Air Ride Suspension Meets 40-Inch Rubber
Although the suspension traces its roots to a 2005 Ford Super Duty, BJ significantly reworked the setup.
Rather than relying on traditional leaf springs or coil springs, the M715 rides on ContiTech air bags that provide adjustable ride height. Bilstein 5100 shocks handle damping up front, while Rancho shocks control suspension movement in the rear. Limit straps help maintain suspension control, and a custom rear track bar fabricated from 1.5-inch-diameter, 0.250-inch-wall tubing adds strength and stability.
The truck rides on massive 40×13.50R17 Pro Comp XTerrain tires mounted to 8-inch-wide Pro Comp wheels, giving the M715 plenty of ground clearance and trail-ready capability.
A CUCV Service Bed Reimagined For Adventure
One of BJ’s favorite modifications is the service body sourced from a 1980s CUCV truck.
Rather than leaving it in its original form, he converted it into a compact overlanding habitat that he describes as “basically a tiny camper.” The setup includes a propane heater, air conditioning, a homemade bed frame, hot water, a shower, a refrigerator, a gas-powered generator, and extensive storage space for extended adventures away from civilization.
The exterior features a custom front bumper equipped with a Smittybilt 10,000-pound-capacity winch, rocker protection with integrated steps, and enough auxiliary lighting to illuminate any trail. Powering part of the electrical system is a heavy-equipment battery rated at 1,200 cold-cranking amps.
Inside, the M715 maintains its rugged military character while adding several comfort-oriented upgrades. Military surplus seats provide seating, while a Vintage Air Gen 4 climate-control system keeps occupants comfortable in changing weather conditions. A full set of Auto Meter gauges monitors speed, fuel level, oil pressure, coolant temperature, and turbo boost.
Built To Explore And Tow
BJ says, “This truck was built more for travel, camping, and lighter off-road use. I also use it to tow my rock crawler quite a bit.”
That rock crawler is a propane-powered 1984 Toyota-based rig running a 22R engine.
The original build required roughly 14 months of work, but like most enthusiasts, BJ continues refining and improving the truck. When he’s not using the M715 for travel or towing duties, he can often be found wheeling at Hot Springs Off-Road Park, Wolf Caves, and Katemcy Rocks, which remain some of his favorite destinations.
Combining classic military styling, turbocharged 6.5-liter diesel power, and a highly functional CUCV camper conversion, BJ’s M715 proves that an old-school diesel-powered workhorse can still tackle modern adventures with ease.
Photos by BJ Kohllepel
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