The Allis Chalmers 645B is a wheel loader produced from 1972 to 1974 as part of the 45 Series. It was built in Deerfield, Illinois, USA, with a total production of 2232 units. It features a 7.0L 6-cylinder turbocharged diesel engine producing 151 hp (112.6 kW) net power, coupled with a 4-speed power shift transmission. The tractor has a 116 inch (294 cm) wheelbase, four-wheel drive with planetary final drives, and articulated power steering. The operator station is open with an optional cab and heater. Hydraulics include a pump flow of 71 gpm (268.7 lpm) and steering flow of 18 gpm (68.1 lpm). The electrical system uses an alternator charging system. Attachments include a front-end loader.