Mack Begins Testing Of Armored Trucks For Army

Mack Defense announced it has delivered six armored Mack Granite-based M917A3 Heavy Dump Trucks (HDT) to the U.S. Army for the Production Vehicle Testing (PVT) phase of its $296 million contract. The trucks will now enter 40 weeks of rigorous durability testing at the U.S. Army’s Aberdeen Test Center.

“Over the past several years, our teams have worked incredibly hard in partnership with the U.S. Army to develop, engineer and begin building these next generation trucks,” said David Hartzell, president of Mack Defense. “We’re confident the armored version will provide the operator protection levels required by the U.S. Army.”

The Mack Granite-based M917A3 trucks are powered by 13 L Mack MP8 engines rated 440 hp with 1660 lb. ft. of torque. The engine package includes a Behr electronic modulating viscous fan drive and Meritor Wabco 37.4 cfm air system without clutch.

The engines are teamed with six-speed Allison 4500 Gen 5 automatic transmissions that drive Meritor MX-810 front axles and Meritor P600/ProTec Series 50 axles rated 76,800 lb. in the rear, with a Fabco TC142 transfer case and  Meritor Permalube RPL drivelines.

The PVT phase of the contract includes a number of vehicle tests to evaluate the trucks against U.S. Army performance and durability. In addition, the trucks will undergo live-fire testing to determine occupant survivability. Non-armored Mack Defense M917A3 trucks entered the PVT phase in 2019.

“Throughout the PVT phase of the contract, the U.S. Army will provide feedback on how the trucks are performing,” said Jack Terefinko, HDT program manager for Mack Defense. “That will allow us to continue to fine tune the program and ensure we’re meeting all requirements.”

The U.S. Army began soliciting bids for a new generation of HDTs in June 2017, seeking to offer increased protection levels, as well as higher payload capacity and improved mobility. Mack Defense was awarded the contract in May 2018, which allows for Mack Defense to produce armor-capable or armored HDTs with deliveries through May 2025.

Based on the civilian Mack Granite model, Mack Defense engineered the M917A3 HDT to meet the current needs of the U.S. Army, while also allowing for evolving requirements and future growth. With heavier-duty rear axles, all-wheel drive and increased suspension ride height, the M917A3 is designed to meet the demanding payload and mobility requirements set by the U.S. Army HDT program.