Mean Green Willys Machine: Matthew McCowan’s 1944 Willys MB

In a world full of shiny JK Wrangler builds, functional and straightforward builds are often shoved to the side. Putting flashy looks to the side for something classic, practical, and rugged is precisely what Matthew McCowan did with his 1944 Willys that he has been building over the last three years. At a quick glance, you might think it’s an old Willys with some simple modifications, but once you dig under the surface, you’ll find that it’s something special.

Starting from the ground up is a set of 37-inch Maxxis Creepy Crawlers wrapped around a set of black Allied beadlock wheels. This set not only looks great, but the Maxxis tires provide excellent traction in the Arizona desert, where this Jeep sees most of its off-road use. The Allied wheels have a simple steel design which fits the simplicity of Willys MB very well, and beadlocks allow Matthew to run much lower tire pressures when crawling. Even with large 37-inch tires, this Willys doesn’t look over-the-top at first glance.

The beadlock wheels not only look good, but they also allow Matthew to run lower tire pressures compared to non-beadlock wheels, which are great​ for rock crawling.

The front axle is a Chevy Dana 44 that has been cut down to fit the size of the Jeep, and it uses chromoly axle shafts, an ARB air locker for maximum traction, and 4.88:1 gears. The rear axle is a Dana 44 out of an International Scout, and it uses upgraded 35-spline chromoly axle shafts compared to the 30-spline shafts it once had. Like the front axle, the rear also uses an ARB air locker and 4.88 gears. “I picked Dana 44s over Dana60s to keep the Jeep light,” said Matthew. “The Jeep only weighs 3,400 pounds, and we just wanted to keep it light and nimble, and Dana 60s would weigh it down a lot.”

Notice the second Willys MB in the background which is a similar Jeep that Matthew built for his father.

Holding those axles to the chassis is a set of Rubicon Express 4.5-inch lift springs which were designed for a YJ, but Matthew made them work on his Willys with a bit of custom work. Dampening all the bumps in the road are Rancho RS5000 shocks at all four corners. During the photoshoot Matthew showed off the impressive amount of flex he was able to get out of those YJ leaf springs, proving that a proper suspension setup makes a world of difference. The steering box is a unit from AGR, which is vastly stronger than the tiny Willys unit this Jeep once used. Plus, it allows for proper power steering, which allows those big 37-inch tires to turn more easily.

Small(er) features like the over-the-knuckle steering improve ground clearance even further, allowing this Willys to clear pretty large obstacles. The YJ lift springs paired with the Rancho shocks allow for great ride quality off-road, something the original Willys MB was lacking.

The suspension is all bolted to a hand-built chassis from Campbell Enterprises. The frame uses 2×4-inch, 0.180-inch wall box tubing, which is all designed around the Chevy LS engine and custom suspension. The chassis also allows for a massive 10-inch stretch, giving this Jeep a much larger wheelbase than a stock Willys. The stretched wheelbase helps it articulate better, improves ride quality, and overall improves how the Jeep handles on and off-road. Sure, the tiny wheelbase of a stock Willys is great for off-roading in tight areas, but a larger wheelbase vastly improves articulation.

Of course, turning those big 37-inch tires isn’t all that easy, even with 4.88:1 gears. The solution to this problem is to use a larger engine that has more horsepower and torque. Like many custom-built Jeeps, Matthew decided a Chevy LS would be the best engine to use in his Willys. This particular LS is a 5.7L Chevy LS1 from a 2002 Corvette. It’s been left stock except for custom-made headers that allow it to fit in the chassis correctly; plus, they make it sound awesome.

Behind the LS1 is a stock T350 transmission. The mostly stock powertrain keeps this Jeep extremely reliable. Although working on Jeeps can be fun, when you already have race vehicles to maintain, having a trustworthy and reliable Jeep is nice. Mated to the T350 is Dana 300 with a 4:1 gear set in it, allowing the Jeep to crawl at very low speed. When combined with the 4.88:1 gears in the axles, this Jeep has a great balance between crawl ratio and road speed.

Thanks to the small proportions of the Chevy LS, it fits exceptionally well in this engine bay.

One of the cool parts of this build is how much it retains the look of a Willys Jeep. Sure, there is a 10-inch stretch which requires custom sheet metal between the tub and fenders, and a custom-built hood, but it still looks like a Willys MB. Part of the reason it still has that iconic look are features like the green jerry cans mounted on the back, the axe and shovel combo mounted right outside the driver’s door entry, and the white lettering on the hood.

Right on that custom-made hood is a big white star, a reference to the military past of the Willys MB. Another cool feature of this Jeep is the foldable windshield glass; it’s great for low-speed off-roading or just letting a little air through when on the road.

The roll cage is a hand-built unit and features a neat little storage rack in the trunk, which is extremely useful considering how little space a Willys MB has. Under the storage rack is a speaker, because no one likes wheeling in silence. Right on the outside of the cage is a small CB antenna.

On the inside of this Jeep, Matthew kept things relatively simple. Still, he updated vital components to bring the 4×4 into the 21st century.

There are five-point harness seats because Matthew wanted to keep it safe. The seats share a very similar color scheme as the outside of this Jeep, helping them blend into the retro looks. The seats also happen to be heated, which is fantastic for those cold mornings! On the dash are Auto Meter gauges and a mix between OEM and stock switches. Connecting the steering wheel to the ARG steering box is a custom-built steering column, made with a piece of aluminum tube and a 3/4-inch shaft in the center. The shifter is an Art Carr unit. “I tried to keep the whole dash factory-looking,” said Matthew. “We tried to keep a lot of the originality on the inside, the glovebox the stock unit, and it still has the rifle mount on the windshield. We just tried to keep it Willys-MB-looking.”

The interior still has a lot of the Willys look and feel, but incorporates modern technologies and luxuries like heated seats.

Most custom-built rigs use coil suspension, which generally articulates more than leaf spring suspension. However, Matthew's Willy has an impressive amount of flex thanks to the YJ lift kit and stretched wheelbase!

All the way up front is a Warn Zeon 8-S winch with an 8,000-pound pulling capacity; no one likes getting stuck, although getting this Jeep stuck would be somewhat tricky, what with all the grip and articulation it has. Sitting on top of the winch is a relatively small LED light bar from Rigid Industries, a great addition for night-time off-roading, which is common in Arizona thanks to the blistering daytime heat.

“When I first got it, it was supposed to be a little Willys MB with a small block in it with stock Dana 44s. We went from there, to wanting fuel injection, so we went and got the LS1,” offered Matthew. “Once we had the LS1, we wanted to stretch it. We realized if we’re going to stretch it we might as well build a custom frame. It went from a little Willys with a small block to pretty much a full custom built Jeep. What was supposed to be a year-long build ended up taking three years. The only thing I would change on it is maybe stretching it four inches between the door entry and the wheel well, so there could be more legroom in it.”

Matthew McCowan is an Ultra4 racer, competing all across the west coast. Professionally, he is in real estate, but he does Ultra4 racing as a hobby. Every professional has their side projects, and this three-year Willys MB build has turned into something quite special. Not only does it look awesome and retro, but it’s reliable and functional. It’s a refreshing thing to see in a world full of shiny JK Wranglers.

It does everything a Jeep needs to do, and more.

About the author

Bryce Cleveland

Bryce has been in the automotive industry for most of his life. He’s done everything from fixing cars, flipping cars, writing about cars, and everything in-between. He has owned a total of 18 vehicles, most of which he owned before the age of 20. He currently drives his 2015 Ford Fiesta ST every single day and has plans to buy his third Jeep XJ Cherokee very soon.
Read My Articles

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