19/06/2025
If you caught the May/June issue of Wheels of Time, you already know the truck—and if you made it to the ATHS National Convention in Madison, you got to see it in person. But for Craig Cox Jr., that 1959 Diamond T 923 isn’t just a showpiece. It’s a rolling slice of history—and still very much a working truck.
“You don’t see them on the road like you do a Peterbilt or a Kenworth. It’s a breed of its own,” Craig says. “You pull up to a truck stop, and people either don’t know what it is, or they tell you a story about one they or their family member used to drive.”
This story started decades ago, when Craig’s uncle, longtime truck mechanic Nate Kenworthy, found the truck on eBay. Once a single-axle dump truck at a Minnesota iron mine, the 923 was built for torque, not speed, with a Cummins 190 and a 5-speed Spicer. Nate gave it a full frame-off restoration, eventually swapping in a Cummins 250 from Fort McCoy and pairing it with a 9-speed Eaton-Fuller. Still, it tops out at 55 mph—something Craig jokingly calls “the sweet spot.”
When Nate retired, Craig stepped in—and got to work. First, he built a steel-pipe brush guard to protect the irreplaceable aluminum radiator. Then came the sun visor (from a 1965 Autocar cement truck), followed by a one-of-a-kind metal sign headliner crafted from discarded Wisconsin road signs—including a historical marker, naturally. Behind the seat? More signs, flipped for a clean, bare-metal look.
Mechanically, Craig’s gone over just about everything—slack adjusters, brakes, bearings, wiring, air and fuel systems, you name it. He even upgraded the exhaust system for that deep, throaty sound that always turns heads. It doesn’t have a Jake, but it doesn’t need one to make an impression.
And no truck is complete without a trailer. Craig found the perfect match in a 1985 45-foot Old Milwaukee Dorsey b**r trailer, straight off Facebook Marketplace. After 16 years in storage, it was pristine—no rust, no fade. He converted it into a mobile lounge, complete with a futon, cafeteria table, pizza oven, and even a vintage school phone booth. The lockers? Salvaged from Wisconsin Dells. The character? All original.
“People offer me double what I paid for it,” he says. “But it’s too cool to part with.”
Craig and his four sons—James, Bristol, Matthew, and Jacob—run the family’s landscaping and lawn care business, Craig and Sons LLC, using the 923 and trailer for hauling brush, hay, and equipment. “It’s in work clothes,” Craig says. “Every dent, every scratch—there’s a story behind it.”
He’s now the VP of the ATHS Southern Wisconsin chapter and also a member of the B**r City chapter. And yes, he’s already planning to bring the truck and trailer setup back to Madison in 2025.
“It’s got trucking history, b**r history—it’s got Wisconsin history,” Craig says. And most of all, it’s still out on the road, making memories.
📖 Want the full story?
Check out the latest issue of Wheels of Time to read the complete feature on Craig Cox Jr. and his unforgettable Diamond T. You’ll need to be a member to get the magazine—but now’s the perfect time to join ATHS and dive into the history, the people, and the trucks that built America.
👉 Join today: aths.org/membership/benefits/wheels-of-time
