The class 59 was the first American-built and the first privately owned diesel locomotive in the UK. Foster Yeoman ordered the first four for their Torr Works quarry since they were not satisfied with the reliability of contemporary British-built locomotives. EMD could offer the requested reliability with their rugged 645-series two-stroke engine that delivered 3,300 hp. The locomotive was basically an SD40-2 that was modified for the British loading gauge and with British brake and cab equipment. It had a load-carrying frame and full-width body whose shape led to the nickanme “Shed”.

The first four class 59/0 locomotives were introduced by Foster Yeoman in 1985 and an order for the fifth one followed. The second customer was ARC Southern which ordered four locomotives, designated class 59/1. Finally, National Power ordered six class 59/2 locomotives. These had special yaw dampers to allow for operation at 75 mph instead of 60 mph. Foster Yeoman 59003 was modified for service in Germany in 1997 and worked there until 2014, when it returned to the UK. The class 66 was the successor of the class 59, featuring the more modern 710-series engine.