A look inside one of America’s most recognizable—and winningest—Limited Pro Stock pulling trucks: Jason Wayman’s 1,600+ hp Mega Cab.
You know the truck. The late-model Mega Cab with the catchy name. When it doesn’t finish out front, it’s usually within inches of winning. Jason Wayman has driven the Megatron Ram to countless First Place distances and multiple PPL points championships over the years. On the Limited Pro Stock diesel truck pulling scene, you won’t find a more passionate, dedicated, or die-hard dirt slinger. Just don’t let his youthful, innocent smile fool you. Jason is as competitive as anyone you’ll ever meet. Winning is everything. Second Place is losing—and losing is maddening.
So, what makes Jason so competitive, and what enables his fifth-gen Cummins to be so dominant? It starts with an incessant drive to win, a sun-up to sundown work ethic thanks to a background in farming, and the high-yielding partnerships he’s formed with some of the best names in the business. It’s a combination that has earned him wins on pulling’s biggest stage, and that’s kept him atop the sport for years. Below, we’re detailing what makes Jason’s 1,600+ hp common-rail Cummins tick and how Megatron continues to be a relentless force, pull after pull, year after year.
If you’re going to grab the competition by the jugular, it takes horsepower to do it—and thanks to the help of Perkins Diesel Jason’s common-rail Cummins turns out plenty of it. The 6.7L-based engine’s block has been filled with concrete and machined to accept fire-rings and a deck-plate. ARP main studs anchor the crankshaft in place, with the crank swinging a set of 1-inch longer, forged connecting rods from Wagler Competition Products. Forged-aluminum Diamond pistons, which keep compression closer to stock than one might expect, complete the competition short block. A Hamilton cam designed to shine at high rpm drives the valvetrain.With the Cummins being machined, assembled, tuned and dyno’d in-house at Perkins Diesel, you can bet the one-off side-draft intake manifold developed for Megatron performs. On the other side of the intake, you’ll find a worked-over 6.7L cylinder head that’s been filled, treated to extensive CNC port work and made to accept fire-rings. Also notice the billet, dual-feed fuel rail in place above the intake manifold. The Exergy Performance piece’s additional feed port accommodates the engine’s dual CP3 arrangement, along with offering a 10-percent volume increase over stock.A pair of 14mm CP3’s from S&S Diesel Motorsport produce the 30,000 psi the injectors see, and both stroker pumps are gear driven courtesy of a Wagler billet front cover. Mounted on the other side of the top CP3, a DSR fuel pump supplies the high-pressure pumps with all the fuel they need. Once through the CP3’s (and the previously mentioned Exergy fuel rail), things culminate with a set of custom Super Mental injectors from Dynomite Diesel Products. The injection system (and the engine itself) is controlled by way of a DID1 stand-alone ECU from Baldur’s Control Systems—a system the folks at Perkins Diesel specialize in.In the Limited Pro Stock diesel truck class, where you’re limited to a single, smooth bore turbo measuring no larger than 76mm (3.0-inches) at the compressor wheel inducer, turbocharger selection is everything. Jason sourced his 3.0-inch charger from Apex Turbo, a ball bearing unit that keeps him neck-and-neck with—and oftentimes ahead of—everyone else. The T-6 charger hangs from a Steed Speed exhaust manifold and produces 55-psi of boost with the engine under full load (and we’ll note that its drive pressure checks in a tad lower). Compressed air leaving the Apex unit is forced through a two-core Chiseled Performance water-to-air intercooler.If you were wondering, there isn’t much left inside the fifth-gen cab… In fact, you can see all the way through to the rear axle from the driver seat. The name of the game in truck pulling is to get as much weight as you can forward of the front axle. So naturally, Jason cut no corners when it came to ditching weight. And when compared to the third-gen Ram that previously wore the Megatron name, Jason tells us this version boasts 400 pounds more up front. With a helper, he can even move the truck around by hand by picking it up at the rear.There is no reinvention of the wheel here, with a familiar combination riding shotgun in Megatron’s cab. A trusty Profab Machine one-speed reverser transmission and quick change transfer case (i.e. drop box) route power to the front and rear axles. Within the Quick Time bellhousing protruding through the firewall, you’ll find a 4-disc clutch from Valair. The Texas based clutch manufacturer has been a longtime sponsor of Megatron, and Jason trusts its products to transfer as much of the engine’s 1,600+ hp through the driveline as possible.No, you’re not looking at a Class 8 truck. This is the rear axle in Megatron: a Meritor 22-145. It came from Kenny’s Pulling Parts & Machine, was made even more robust thanks to gun-drilled axles and a spool, and sports a 6.20:1 ratio ring and pinion. Up front, Jason relies on a Dodge Dana 60 that’s been rock-solid reliable for a number of years. It’s been treated to a Detroit locker, 300M axle shafts, and also had its ball joints deleted thanks to a spherical bearing system from American Iron Offroad.After Megatron drove into the winner’s circle wearing a set of Kenda Klever M/T2’s back in 2024, he turned to them full-time—and so did a lot of other pullers. Tire choice has long been one of the most unsettled variables in truck pulling. Some swear by Nitto’s Mud Grappler, others have made the switch to these, many run a combination of both, and some still even trust the old-school BFGoodrich A/T’s to get them to the front. For 2026, Jason is sticking with his 315/75R16 Kenda’s all the way around. They’re mounted to 16×12-inch Real Racing wheels—wheels that weigh just 7 pounds apiece.Born and raised on a ranch in northeast Missouri, Jason grew up a cattle farmer. But not long after the truck pulling hobby entered his life he opened his own diesel repair shop roughly 10 years ago. No Way Man Diesel, a witty play on his last name, now enjoys a large and ever-expanding customer base, while Megatron enjoys a loyal fan base. It also means a lot of hours are spent in the shop on top of all the hours on the road traveling to events during the summer months.Some might not know that Jason’s fifth-gen is actually the second rendition of Megatron. The original version was an ’06 Mega Cab, which initially competed without a wrap and was Jason’s daily driver. To piece this one together, he enlisted the help of a friend at St. James Auto & Truck Parts. “There are about five trucks in this one build,” Jason told us. He calls it a 2022 model year, and a 2500 series. To say this truck was an immediate hit on the pulling scene when it debuted in 2023 would be an understatement. Fans loved it.Jason’s easygoing demeanor in the pits in no way indicates his intentions out on the track. From inspecting the track to setting up the truck, and picking the right line to executing a solid A to B pass, Jason is dead serious about his truck pulling. Look no further than what he and Megaton did from 2022 to 2024. For three consecutive years, he won the Pro Pulling League Champion Seed Western Series 3.0 points championship. In 2025, he finished second (along with earning the runner-up spot in the Outlaw Truck and Tractor Pulling Association).Always on a mission, Megatron rarely finishes outside the top trucks in the Limited Pro Stock class—even when dozens of the nation’s strongest running 3.0 candidates show up. Putting all that horsepower to good use, and depending on the track, Jason will run an 11:1 final drive to build some serious ground speed. Sometimes Megatron’s final drive even checks in at an incredible 10.7:1 ratio. According to Jason, he’s been as fast as 35-36 mph in the past. Each hook, he leaves the line between 4,200 and 4,500 rpm and attempts to carry roughly 4,000 rpm down the track. “I like to lug this truck, and the engine makes great power down low, which works out well on a biting track,” he said.Of all the wins Jason and Megatron have accumulated over the years, this is perhaps his favorite one. Back in the original unit, the ’06 Mega Cab stole the show at the Scheid Diesel Extravaganza (back before SDX left Terre Haute in 2020). The blockbuster weekend kicked off with a First Place finish on Friday, and he returned with a Second Place performance the following night. Between having to qualify to make the nighttime show on Friday and going up against 60 other trucks on Saturday evening, it was a roller coaster of a weekend he’ll never forget.
