In part inspired by LMS prototypes 10000 and 10001, and by Southern Railway 10201-10203, the Class 44 diesels were some of the first big diesels commissioned for the British Rail modernisation project and were the precursors to the Class 45 and Class 46 locomotives of similar design. When initially put into service the locomotives were fitted with multi-unit working and steam heating boilers for passenger service. They worked regularly over the West Coast Main Line for a couple of years, also between St.Pancras and Manchester. Once the Class 45 units were available the steam heating boilers were removed and the Class 44 locomotives were assigned to freight duties, largely in the East Midlands where they were all based at Toton, where they stayed until 1980.