The London, Midland and Scottish Railway pioneered the use of dieselshunting locomotives in Great Britain. The variety of experimental and production diesel shunters produced by the LMS is summarised below. In each heading, the first number carried are shown first, with subsequent renumbering following the "/".
Note on numbering
The initial experimental diesel shunter retained the number of the steam locomotive that it was nominally rebuilt from. However, when the LMS decided to procure a further nine prototype locomotives from a variety of manufacturers, it allocated the number series 7400–7408 to them. It was soon realised that this number range was too limited for the number of production diesel shunters that were anticipated, and a new series commencing at number 7050 was used. Only 7050–7053/7058 carried their original numbers, and they were all renumbered in November/December 1934, some before they had actually entered service.
1831
This was the original experimental shunter, nominally rebuilt from a Midland Railway steam locomotive originally built in September 1892 by the Vulcan Foundry, whose number it inherited, though very little of the steam locomotive was actually re-used. Of itself, it was not very successful, but it did provide useful data for the further development of the diesel shunter design. It was withdrawn from service in September 1939 and converted to a mobile power unit, emerging in its new guise as MPU3 in November 1940. It was scrapped in the 1950s.
NB: Production of the last-mentioned class continued after Nationalisation, with the following two locomotives emerging as M7130 and M7131 and the remainder carrying BR numbers 12045–12138 from new. Although allocated TOPSClass 11, none of these locomotives were renumbered. When 12082 was re-registered for use on the mainline, it was allocated TOPS number 01553 in the ex-industrial registered shunters list.
The LMS used a number of locomotives on loan from their manufacturers for trials. These locomotives were not allocated LMS numbers, and details of their use and disposal are sketchy. Such locomotives included:
Vulcan – a diesel-mechanical 0-6-0 shunter built at the Vulcan Foundry, Newton-le-Willows, in 1936. It had a Vulcan-Frichs 6-cylinder diesel engine. After loan to the LMS, it was used by the War Department, which numbered it 75. Following the end of World War II, it found industrial use in Yugoslavia.
– an Armstrong-Whitworth/Sulzer shunter built in 1932, which was an earlier version of the LMS's own 7408/7058. This locomotive was also loaned to the London and North Eastern Railway for trials.
