The next ‘Large Prairie’ in the sequence, No. 3150, was built with a Standard No. 4 boiler – the same as the one fitted to Churchward 2‑8‑0Ts and ‘City’ 4‑4‑0s – in 1906. In all other respects, it was identical to the preceding locomotives, even retaining the 5ft 8in diameter driving wheels. A further 40 (Nos. 3151‑3190) were built in 1907/08, with larger cylinders (18½in by 30in). The class was used for banking, which required bracing struts from bufferbeam to smokebox to help beef up the front end. This feature appeared on all GWR locomotives with leading pony trucks. The last ‘3150’ withdrawn was No. 3170 in 1958.