A noticeable feature of design is the backwards sloping cab front. It was made so that as little of the boiler is inside the cab in an Attempt to reduce the heat in the cab. The class worked for 20 years. The introduction of diesels cut short their lives. As early as the mid 50s diesels were working all lines in the drier part of the state. When withdrawn most were still in good working condition. 15 went into preservation, many of them to operate passenger trains.

W901 in service 1951 and withdrawn in 1972. Purchased by the Steamtown group in Peterborough and arrived in 1979. Overhauled and put in service on the Peterborough to Orroroo line. This line closed 1987 to freight, the last tourist train ran in 2002. Being to expensive to maintain, this line was lifted in 2008. W901 is now an exhibit at Steamtown roundhouse. W901 is in a part of the roundhouse that was used for diesel loco maintenance so you can inspect the motion, then climb up to the platform running at footplate level. It stands on a pit, but that not accessible.