Test it Out: Mack Defense Begins Production Vehicle Testing Phase with Armored M917A3
Mack Defense Shows Off Heavy Dump Truck
Based on the commercially available Mack Granite model, the Mack Defense HDT is part of the previously announced firm-fixed price $296 million contract with the U.S. Army to be fulfilled over seven years.

Mack Defense will feature a production M917A3 Heavy Dump Truck (HDT) at the Association of the United States Army (AUSA) 2022 Annual Meeting and Exposition in Washington, D.C.
Photo: Mack Trucks
Mack Defense will feature a production M917A3 Heavy Dump Truck (HDT) at the Association of the United States Army (AUSA) 2022 Annual Meeting and Exposition, Oct 10-12, at the Walter E. Washington Convention Center in Washington, D.C.
Based on the commercially available Mack Granite model, the Mack Defense HDT is part of the previously announced firm-fixed price $296 million contract to be fulfilled over seven years that the Army awarded Mack Defense in 2018. Mack Defense began production of the HDT vehicle in 2021 at the Mack Experience Center in Allentown, Pennsylvania.
This will be the first time that a production version of the Mack HDT is on display at AUSA and is one of many the U.S. Army is purchasing and fielding to the Army, Army Reserve and the National Guard.
“We are proud to publicly show a production version of the Mack M917A3 HDT for the first time at AUSA,” said David Hartzell, president of Mack Defense. “The response has been very positive, and we look forward to continuing to build these trucks to meet the U.S. Army’s demanding operational requirements with a modified commercial-based vehicle.”
Getting to Know the Mack Defense M9173A HDT
When it comes to specifications, this heavy-duty defense truck has what the military needs:
GVW: 94,500 lbs.
Wheel Configuration: 8x8
Frame: 300mm X 90mm X 11.1mm with steel reinforcement frame
Wheelbase: 243"
Platform: 230"
Mack Defense optimized the M917A3 HDT to meet the current performance needs of the U.S. Army, but included modularity in the design, to more easily adapt to evolving requirements. Mack Defense engineers added heavier-duty rear axles and all-wheel drive, while increasing the suspension travel and ride height to create a heavy dump truck capable of meeting the demanding payload and mobility requirements set forth by the U.S. Army HDT program.
Powered by a Mack 13.0L MP8 440, the truck achieves 440 hp at 1,660 lb.-ft. of torque.
The HDTs are a key component in construction and maintenance missions for infrastructure assets, such as airfields, roadways, landing strips, supply facilities and motor pools.
Built on the Mack Granite, the HDT model is a modern truck equipped with state-of-the-art technology, such as an anti-lock braking system (ABS), back-up camera, blind spot sensors, and inclinometer to ensure safe dump operations.
The Granite model is user-friendly, more comfortable and safer to operate than past models used by the Army, which is key to the Army’s investment in the new HDTs. The Granite HDTs and assembly processes were inspected by the government’s quality auditors to ensure expectations were met or exceeded.
Prefer to watch? Check out this video for more details on the Mack Defense M917A3 Heavy Dump Truck:
Mack Defense is a member of AUSA, which has a vision to be the premier voice for American soldiers. AUSA is committed to building the best professional and representative association for the U.S. Army. More than 30,000 attendees visited AUSA in 2021, with 700 exhibitors representing 100 countries from around the world.
Looking Back
Mack Defense began producing Heavy Dump Trucks (HDT) at the Mack Experience Center in June of 2021, following an investment of $6.5 million to create a dedicated production line at the facility. Not stopping there, the automaker partnered with TenCate Advanced Armor USA to provide a force protection system for the Mack Granite-based M917A3 Heavy Dump Truck (HDT) and other Mack Defense vehicle platforms.
The truckmaker was originally awarded a $296 million firm-fixed price contract to be fulfilled over seven years. In August of 2022, the U.S. Army placed an order for 144 more trucks from Mack Defense.
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