They were built in 1959 at Wolverton Works, and the body was a standard type used for several electrification schemes of the time, but the high DC voltage through a side-contact third rail was unique in Britain.

[7] The trains replaced the previous five-car units built by the Lancashire and Yorkshire Railway (LYR) for the route, which had inaugurated this electrification scheme in 1916.

All were withdrawn in 1991 when the line was closed for conversion to form part of the Manchester Metrolink light rail system.

In 1986, a condemned vehicle (possibly 77169) was given (on temporary bogies) to the newly formed East Lancashire Railway (ELR).

By the 1966 LMR timetable, only 6 to 7 years after the units were introduced, the peak hour service was down to a 10-15 minute interval.

Additionally, Driving Trailer 77164 was transferred to the Tilbury lines of the Eastern Region 1970 to replace car 75292 in 302244, which had been written off in an accident.

65436 and 65437 were used as the depot shunting set for a time, having had some front wiring and internal fittings removed, and were repainted in plain blue with yellow ends.

After being stripped for spare parts at their southern locations, three cars (Blue 65436/443 and Green 77158) were dumped at Cockshute in Stoke-on-Trent in sight of the West Coast Main Line.

Two units remained at Bury, one purchased for the East Lancashire Railway, and another bought, reputedly as a joke, for £504 by Harry Needle Railroad Company.

This was a major success for the October diesel gala, and pointed numerous possibilities to the future for having two units.

[9] A new Class 504 preservation society was launched on 8 November 2015,[10] and work on restoring the units began on 24 January 2016.