BroDozer: The Road to Nashville

Authored by Larry Jewett on July 12, 2018


Diesel Technology Comes to Monster Jam

The idea has been kicked around for decades, maybe even from the beginning of what we now know as “Monster Trucks”. Since that time, it has been a hot topic when gasoline prices were skyrocketing and the idea of using fossil fuels was looked upon as a senseless practice. Then, gas prices come down and the idea of alternate fuels falls out of vogue. The question still remained – can there ever be a diesel-powered Monster Jam truck?

For innovators, though, the phrase “it can’t be done” is like nails on a chalkboard because there is no suitable answer to their “why not?”. For the time being, there were other matters to deal with in research and development that occupied the front burner. Diesel would have to wait.

The proper time has come and a concerted effort to develop a competitive diesel engine to power a Monster Jam truck has begun. In fact, that engine made its competitive debut in Nashville, Tennessee on June 23, 2018 beneath the body of BroDozer. History has been made, but there is plenty of work to be done before this project is called complete. The first few chapters have been written, but many more remain for the rest of the story.


The choice to create a diesel-powered Monster Jam truck was not done just to do something no one else has done. There have been diesel-powered Monster Trucks, but several factors had to be considered in order for the truck to compete in Monster Jam. Some, but not all, factors included safety, parity in competition, knowledge of performance and environment. Besides, diesel didn’t seem all that popular among the masses in the U.S. That doesn’t hold true for the rest of the world.

According to the European Automobile Manufacturers Association, 45 percent of vehicles in Western Europe were diesel-powered in 2017. The market reached 40 percent in 2002 and has not dropped below that mark since. For the most part, U.S. car buyers have not embraced the diesel technology for their daily drivers. The strongest market is arguably found in the purchase of diesel-powered trucks, but even they lag behind the gas-powered models.

Studies have shown diesel emissions contain less carbon dioxide than a typical petrol-powered vehicle. Continued legislative efforts like the Diesel Emission Reduction Act of 2009 in the U.S. and similar measures in the European Union have assisted manufacturers in staying in the good graces of environmentalists.

Diesel engines are lean combustion engines, which means they have a consistently high air-fuel ratio. As such, formation of carbon monoxide (CO) is minimal. Since diesel engines get better fuel economy, studies have shown the engines produce less carbon dioxide (CO2) than a typical gasoline-powered engine.


The idea of a diesel-powered Monster Jam truck received a boost when Monster Jam’s Triple Threat Series visited Salt Lake City in January 2017. Heavy D and Diesel Dave, stars of the Diesel Brothers television program on the Discovery Channel and proprietors of Diesel Sellerz, were in attendance. The mutual interest led to increased discussions of the possibility of creating a diesel-powered Monster Jam truck. The Diesel Brothers had created their own off-road vehicle called the “BroDozer” and that concept seemed a suitable one to take to the Monster Jam level.

Wagler Competition Products was recruited to be at the forefront of engine development. Due to the unique nature of the build, there was little that could be used for exacting reference, but Wagler has extensive experience in competition diesel for drag racing and pulling and some of that knowledge would translate.

The first idea called for utilizing the supercharger system in place at this time on all methanol-powered Monster Jam trucks. The tests did not reach the desired numbers, so an alternative was sought. The tried-and-true compound (stacked) turbos proved to be the combination that pushed the project to the next step.




The engine’s performance numbers would be a major factor in the success of this project. The strength of diesel power rests with torque numbers. While horsepower is the figure most fans see in relation to Monster Jam trucks, the torque produced by the engine is the driving force in propelling the truck. Torque is a measure of force that can cause an object to rotate about an axis. In the case of a vehicle, dynamic torque produces angular acceleration of the wheels. The sheer size of those wheels on a Monster Jam truck provides a good indication of the force needed.

The engine development continued with the goal of reaching a torque number, measured at the flywheel, that was identical to the torque created by a methanol-powered Monster Jam engine (1,320 lb-ft). The engine would also need durability to withstand the extreme punishment required for competition.

After extensive research and development, working with parts combinations that have been tested in high performance applications, an engine was created that met all of the desired goals. The heart of the beast is a Wagler-built 6.6-liter Duramax that uses tuning and fueling components from S & S Diesel Motorsport. Turbocharging is in the hands of Precision’s GEN2 6870 designed for greater efficiency at higher pressure ratios. Fuel is delivered by a Waterman pump through S & S Diesel-supplied LBZ injectors and a pair of 10mm CP3 injection pumps. A Bosch electronic control system serves as the mastermind.


Once the engine package came together, the powerplant had to perform in real world conditions. The engine was fitted into a Monster Jam chassis and delivered to Monster Jam University in Paxton, Illinois. In addition to the stresses and strains of cyclone donuts and big air stunts, developers were cognizant of emissions. Diesel smoke has the perception of being “dirty”, thanks to the dark coloration. Globally, there have been long-running efforts to remove harmful particulates from emissions and filters have been employed to result in cleaner emissions. The smoke is seen on the initial acceleration, but dissipates throughout the run during the truck’s competition.

During the testing, the fuel efficiency was immediately obvious. During a week of testing that would require a 55-gallon drum of methanol, the diesel-powered engine required just 10 gallons. A typical methanol powered Monster Jam truck will expend 10 gallons in a typical show. At the rate found at testing, the diesel-powered engine will require 20% of that.

Again, because of the unique nature of Monster Jam competition, every day was another step into uncharted territory. The engine components were subjected to substantial increases from normal. For example, a “normal” turbocharger” will usually see up to 15 pounds of boost, but these units would achieve over three times that amount.


After the Paxton testing was completed to the satisfaction of all parties involved, it was time for the debut. The June Monster Jam event in Nashville became the target date. The truck was subjected to extra practice time to acclimate the new driver, Heavy D, who could parlay his diesel-driving experience with the previous Monster Jam testing at Monster Jam University. The truck was quick right out of the gate, performing within tenths of a second in running the Racing course.

As the show progressed, the BroDozer continued to showcase its competitive chops. Heavy D’s valuable time at Monster Jam University provided the basis for a confident and competent performance in real conditions. The BroDozer Freestyle score spent time atop the leaderboard, eventually slipping to fourth, but the three drivers with better scores on that night have 18 World Championships on their resumes.


Here's what the fans and drivers had to say.



There were plenty of lessons learned about the engine performance through the Nashville event. The diesel-powered Monster Jam engine is a work in progress that has room for improvement in a few areas, all the while keeping the playing field level. It’s no different than any other Monster Jam project as organizers are constantly searching for new and better. Safety, efficiency and environmental issues have long been addressed proactively. The final chapter in the diesel-powered Monster Jam truck is well in the future. Stay tuned for the latest developments here at www.MonsterJam.com.

Wagler Competition Products

S & S Diesel Motorsport