Mack Defense, an arm of Mack Trucks, built several of these prototype M915 military-grade linehaul tractors – based on the OEM's Granite chassis – a few years back to compete for a U.S. Army vehicle competition that never got off the ground. Yet this “next generation” M915 caught the eye of filmmakers, who used one to play the role of the nefarious “Megatron” in the third installment of the “Transformers” movie series.