In this month’s Monthly Military, we’re taking a look at another BMY M923A2. This one sports the “Franken Cab” layout, a design with considerations made specifically for personnel transport.
The M939 five-ton trucks have been a staple in military service due to their flexible design. This allows the trucks to take on multiple tasks, from hauling ammunition to moving personnel into the battlefield to performing recovery missions; sometimes all three. This particular vehicle is configured with personnel transport in mind, and utilizes additional armor throughout the body, while its 20,000-pound winch up front and 105mm gun mounted on the roof allow it to perform high-risk recovery tasks as well.
Part of the M939 series of transport trucks that were developed in the late 1970s to replace the outgoingM39 and M809 series, this M923A2 weighs in at about 26,000 pounds and is powered by a Cummins 6CTA 8.3-liter turbocharged motor that is tuned to make around 300 hp and 800 lb-ft of torque.
That output isa substantial performance upgrade from the 240 hp and 716 lb-ft these motors make in stock configuration, and this tuned powerplant utilizes an EGT and aboost gauge kit to prevent any possible damage.
The Cummins 6CTA 8.3-liter turbocharged motor in this truck has been warmed over, and now outputs 300 horsepower and a hearty 800 lb-ft of torque. It utilizes a custom-designed air cleaner to improve airflow. Bill from Those Military Guys explains that while there's room for additional output, they've set up the motor as it sits now for the sake of reliability.
That motor is hooked to an Allison five-speed automatic transmission and a two-speed transfer case to get the power to all six wheels through three five-ton Rockwell axles.
M923 variants of the M939, such as the one we’re looking at here, were specifically configured for cargo transport and featured a body with drop sides so it could be loaded from the side by forklifts. These “Franken Cab” trucks were configured as such to be driven directly into combat zones while transporting troops, so these versions of the M923A2 also utilize a number of reinforced elements to protect the personnel in the vehicle. This particular example was kept in California during its time in service for National Guard use.
The truck’s suspension design consists of a leaf spring front end and floating tandem rear axles. Generally, full floating axle designs are reserved for vehicles that are built for severe duty or heavy hauling, and the M923A2 fits the bill for both. This type of axle uses an axle shaft on each side that is either splined at both ends or splined on the inner end and has a drive flange on the outer end.
Part of the charm of the M923 is its modular design and ability to be utilized for many different tasks, and this particular M923A2 showcases those attributes well. Along with personnel transport, it’s been configured for hauling as well as recovery tasks, hence the 20,000-poundwinch that is installed on the front of the truck,and the 105mm cannon mounted on the roof to keep would-be attackers at bay.
Operation of the truck's 20,000-pound winch is made easier by a front mounted camera that allows the user to see the front winch while in operation. Ease of visibility while performing tight maneuvers is also improved by that camera, as well as another one installed in the rear. We can only imagine what a welcome addition that is when attempting back this beast up into a parking space.
A heavier gauge metal was utilized in the rear cargo area of the vehicle for added protection, and all of this truck’s body seams are fully welded. Since transitioningto civilian duty, this truck has seen a number of upgrades from Those Military Guysin Rancho Cucamonga, California, who specialize in repairing and upgrading heavy-duty hardware like this M923A2.
Another key feature of the A2 variant is the central tire inflation system (CTIS). This system provides control over the air pressure of each tire on the fly in order to improve its performance over varying surfaces, thereby substantially increasing the truck’s maneuverability. The CTIS also allows the driver to maintain air pressure in the event of a puncture so that the vehicle can still be driven with a slow leak. Considering the fact that each one of these tire and wheel combinations weighs several hundred pounds each, this functionality is vital out in the field. This M923A2 is equipped with 50-inch Goodyear rubber.
“We made it taller so a 6-foot-tall person can stand upright and still have room above his head to walk around,” says Bill Dozer of Those Military Guys. It’s also equipped with a full roll cage and an under-cab roll cage. It even has an armored roof with a hatch for access to the gun turret, along with a standing platform for the operator to stand on to fire the weapon.
This hatch installed on the roof of the cab allows for access to the roof, where a stand was installed to allow the turret operator to use the gun while standing on the roof of the vehicle.
There are also a number of interior upgrades to make this M923A2 a bit easier to live with, including a raised cab, air seats, and a completely redesigned dashboard. But there’s still some room for additional upgrades down the roadif required. “This truck weighs in at around 26,000 pounds, so we didn’t turn the horsepower up nearly as much as we could,” Bill explains.
This M923A2 sports a redesigned instrumental panel versus the stock layout, one which provides vital boost pressure information to the driver so they can monitor the modified engine's vitals while in operation.
Keep your eyes peeled for next month’s Monthly Military installment, where we’ll be taking a look at another icon from Uncle Sam’s roster of transport vehicles.
