The Big Bud KT400 is a four-wheel drive farm tractor produced by Big Bud from 1977 to 1978. It is part of the KT Series and was built in Havre, Montana, USA. The tractor is powered by a Cummins 18.8L 6-cylinder turbocharged diesel engine producing 450 hp (335.6 kW) at 2100 RPM. It features a Fuller Road Ranger 13-speed transmission with 13 forward and 2 reverse gears. The KT400 has a 4x4 4WD drive system with hydrostatic power steering and a standard cab. It weighs 40,000 lbs (18144 kg).