The LMS was the only British railway to order greater numbers of large Garratts. Although the Midland Railway's small engine policy had worked for most of the time, they needed much more powerful locomotives when even double-headed 0-6-0 locomotives became overwhelmed by heavy coal trains. They had to haul trains of 1,450 tons with a speed of 25 mph (40 km/h).
Three were built in 1927, followed by 30 more in 1930. Only one year later, 31 were fitted with the Beyer Peacock Patent Self-Trimming Coal Bunker. These cylindrical bunkers were revolved and oscillated by means of a two-cylinder steam engine, conveying the coal to the cab. These also reduced coal dust in the cab, but often got jammed.
One problem was the standard axle bearings designed by Derby, which the LMS insisted on and which turned out to be too weak. Another finding was that these locomotives were heavy on coal, even measured by their huge pulling power. Despite these issues, there were only retired between 1955 and 1958. They were replaced by locomotives like the BR Standard 9F that had a similar pulling power, but could also reach higher speeds with lighter trains.