U.S. Army LARC In 1952, Lighter Amphibious Resupply Cargo amphibious vehicle, capable of carrying a 60-ton tank, made its maiden voyage in Washington state. Gross weight fully loaded: 319,000 pounds. One GMC 265-hp marine diesel engine powered each of the LARC-60's nine-and-a-half foot tall Firestone tires. The same four engines were used to drive two propellers in the rear via a transfer transmission. The 17-foot tall, 63-foot long LARC can travel at 20 mph on land and 7 mph in the water.