SEMA’s Best Diesels
Three top-notch builds from SEMA, GM loses its license to use Allison trademarks, Jelibuilt’s next 7.3L Power Stroke, and a Wyoming diesel mechanic receives a presidential pardon.
Compression ignition always seems to have its own special place at the annual SEMA Show, and 2025 was different with three top-tier diesel builds catching our eye. First came the show-stopping ’52 Power Wagon creation from Six Twelve Auto Worx, complete with a 2013 Ram 2500 chassis underneath, a 6.7L Cummins under the hood, full air ride, and an unbelievably time consuming hand-fabricated body. Then there was the late-model Silverado 1500 that had been converted from a double cab to a regular cab and had its 3.0L LZ0 Duramax fitted with a Jstar Fabrications compound turbo arrangement (S300/stock VGT). And who could forget Sterling Diesel Performance’s masterpiece of a ’72 C10, the one with a twin-turbo Duramax, fully restored body, and a shortened ’07 Silverado 2500 HD chassis underneath.
OEM News
No More Allison Badging For GM’s HD Trucks
It’s the end of an era. General Motor’s license to use Allison Transmission trademarks on its HD trucks expires on December 31st. GM and its authorized dealers have until June 30, 2026 to market, advertise, and sell their remaining inventory bearing the Allison name. No, dealers are not de-badging trucks currently sitting on their lots. They have until the end of June to sell them. After that, it’s a brave new world—one where a “Duramax” badge is likely all that’s displayed on the cowl. Full Disclosure: The Allison side of this badging essentially ended when the 10L1000 debuted in 2020 (with Allison merely approving GM’s new 10-speed design rather than actually building it).
Competition Engine
Jelibuilt’s New KDD 7.3L Build
After Brian Jelich split the block of his 1,400+ hp 7.3L, he wasted no time making his next move. Now, the owner of Jelibuilt Performance has a whole new animal being pieced together at Kill Devil Diesel. A Hypermax Engineering compacted graphite iron block will house a bombproof bottom end thanks in part to a Hypermax bedplate, Carrillo rods, and fly-cut Mahle Motorsport pistons. Clevite H-series bearings, ARP main and head studs, and Kill Devil’s Delta Series CNC-ported heads (shown) are all on the build sheet as well—along with a race-spec camshaft from the late Brian Gray. Look for this (HEUI-fired) 7.3L Power Stroke to push Brian’s Super Duty into the 4’s next season.
At The ‘Strip
Turbos & Tailgates
The first Turbos & Tailgates race was held at Wilkesboro Dragway over the weekend, and we think it’s safe to say this will be a regular affair in western North Carolina. Everything from 7.70 and 6.70 Index to an Outlaw class was run, with ODSS racer Skylar Fornes bringing his 5.70 Index Cummins to the gate and taking home wins in the latter category as well as Singles Elite. For Skylar, the day peaked when his third-gen went 5.82 through the ‘660 on fuel, a new personal best. If you recall, Skylar won a tight points championship this season in the ODSS 5.70 Index class, emerging as one of the series’ premier drivers.
Emissions
Imprisoned Wyoming Diesel Mechanic Pardoned By President Trump
The choice was clear for Troy Lake: make his customers’ diesel-powered equipment and vehicles more reliable by removing emissions equipment or keep taking their money for repeat failures. The EPA didn’t see it that way, fining Lake and his business, Elite Diesel of Cheyenne, Wyoming $52,000 and ultimately sending him to prison. This year, the 65-year-old Lake spent seven months in federal prison, followed by home confinement. Last week, he got a call from U.S. Senator, Cynthia Lummis of Wyoming, who informed him he’d been pardoned by President Trump. It’s welcomed news for a repair industry that’s unfortunately been forced to choose between expensive, failure-prone “legal” fixes and permanent “illegal” solutions for its customers.
Written by Mike McGlothlin
