You probably know Banks Power from their high-power diesel projects, like the GMC Sierra Sidewinder Type R track truck, or the diesel S10 that runs 7s in the quarter mile. Those kinds of enthusiast builds helped cement Banks as one of the premier diesel tuners in the world, which in turn helped them win a government defense contract in 2022. The U.S. Army’s Rapid Capabilities and Critical Technologies Office asked Banks to develop a new drivetrain for the old HMMWV to bring it into the future.
Colloquially known as the Humvee, the AM General-developed military truck has been in service since 1983, and is in desperate need of a revamp. A bit over a quarter million of these big trucks have been built over the last forty years, and the long-serving 6.5-liter non-turbo diesel V8 under the hood is proving inefficient and incapable of supporting a modern armed forces. The most common examples of the HMMWV make an astonishingly low 195 horsepower and 380 lb-ft of torque, giving them a top speed of just 55 miles per hour when loaded down.
The primary purpose of the contract was to integrate hybrid technology into the old truck, bringing the antiquated platform into the modern age. The hybrid battery can not only assist the truck with better acceleration and top speed, but it can also be used to power a mobile tactical operation center, and potentially support future weapons systems.
Banks developed a new hybrid drivetrain for the HMMWV which ditches all of the stock components in favor of a modernized diesel-electric combination. The 6.5-liter V8 has been swapped out for a 3-liter V6 and a turbocharger, which not only makes more power, but burns less fuel. Behind it, the transmission tunnel incorporates a robust electric motor. The new drivetrain improved acceleration, range, and speed, while improving the aging platform’s capabilities.
According to Banks, the prototype exceeded the Army’s requirements for acceleration, range, and braking. Perhaps the most interesting part of the experiment is the ability of the prototype to operate in a silent full-EV mode and still beat the Army’s requirements.
Now that the prototype has been finished and Banks has done some internal testing, it has been handed off to the Army for further study. No final test results have been released on the hybrid Humvee yet, but Banks promises future releases about the project, which will hopefully give us an indication of the restomodded troop transporter’s acceleration numbers and fuel economy.
In 2022 the Department of Defense purchased an estimated $10.3 billion in bulk diesel fuel. The U.S. military consumes about 622.5 trillion Btu of energy annually (though this statistic is steadily dropping), which is almost 13 times more than the U.S. Postal Service—the second-highest consuming government agency—uses. Making the Army’s 100,000-ish Humvees a bit more efficient would make a small drop in that ocean of fuel consumed, but it’s not nothing.