A Duramax and Allison-Swapped 4100 Series Chevrolet
It was supposed to just be a work truck, but for Phil Prinster—a man that’s made his old Oliver tractor so nice it no longer handles his brush-hogging duties—functionality alone wouldn’t suffice for his ’50 Chevrolet 4100. Once a part of the St. Louis metropolitan district fleet, the truck also served as both a milk and grain hauler for a period before Phil acquired it from a friend roughly three decades ago. For years, he never could quite decide what he wanted to do with the 1.5-ton Chevy, but then he got an idea.
Modernizing A Classic
Instead of doing a run-of-the-mill small-block build or dropping a big-block into the old truck, Phil decided a Duramax was the way to go. But rather than simply source an engine and transmission for the project, he picked up a wrecked ’06 Silverado 2500 and based everything on the HD’s modern era chassis, axles, and suspension. With help from his son Andy, son-in-law Josh, a host of local, small-town businesses, and the support of his wife of 41 years, Bonnie, Phil had the project wrapped up in a little over two years’ time.
Prior to sending the 4100 to his local auto body experts, Phil performed a bit of welding, filling holes on the exterior and along the firewall, as well as replacing both cab corners. From there, Outlaw Customz of Moscow Mills, Missouri took over. When it was time to paint the truck, it was sent over in pieces—first the MAR-K bed, followed by the cab, and then the front clip. The folks at Outlaw came up with the one-off paint color, too, which can only be described as being close to resembling a black cherry with a healthy amount of metal flake.
LBZ and Six-Speed Allison
Being that Phil wasn’t after making big horsepower with the project, the 200,000-mile LBZ Duramax and six-speed Allison were left untouched. As for the engine, it cleared the ’50 firewall by a mile but required the radiator be relocated. As for the Allison, raising the cab a couple extra inches above the frame helped Phil avoid any clearance issues. Nearby LinCo Diesel Performance helped ease the Duramax/Allison integration by installing a Standalone Solutions wiring harness, as well as a single EFI Live tow tune from PPEI to help wake up the LBZ. The factory ’06 transfer case, an NP261XHD, is still in the mix, too.
All HD Underneath
The frame, front and rear suspension, and receiver hitch from Phil’s ’06 Chevy donor were all salvageable and are currently in use. To accommodate the shorter body of the ’50, the frame had to be shortened, but neither the rear AAM 1150 and its leaf springs or the front AAM 9.25 IFS were affected. In fact, even the factory ’06 front skid plate is still employed. Retaining the bolt-in style OEM receiver hitch was mandatory, being that Phil uses the truck to haul steel for his business several times a month.
While various mechanical upgrades have been made, the interior remains true to its roots, with the original dash and a bench seat. A SureFit air conditioning system from Vintage Air and a stereo from Custom Autosound complete with a slidebar radio add a few creature comforts, while a Flaming River steering column and Speedway Motors steering wheel replaced the original components. The bench seat consists of a Glide Engineering frame purchased through Walton Fabrication, which both reclines and flips forward, providing a significant amount of under-seat storage. The seat was upholstered locally by JCAT Customs. For sound deadening, X-Mat insulation from Eastwood got the call.
Tow or Show
Making the project a family affair with his sons, along with enlisting the help of local shops whenever possible, definitely made the undertaking all the more special. But even though Phil has put together one of the nicest diesel repowers we’ve come across, he doesn’t plan to deviate from his original plan of using the truck to tow. Of course, the occasional trip to the local car or truck show is on the list as well. Rest assured, whether it’s earning trophies or earning its keep, Phil’s one-of-a-kind ’50 Chevrolet will get driven—and of course attract attention wherever it goes.