The class C36 was a 4-6-0 express locomotive that had been developed from the C35. All were built in Australia, ten by the NSWGR's Eveleigh Railway Workshops and 65 by Clyde Engineering. Like the C35, they were superheated from the start, but they had a round-topped firebox instead of a Belpaire-type one. For the first time in Australia, they were built with outside Walschaerts valve gear. Although they had good running characteristics, claims of speeds of 150 km/h (93 mph) or even 160 km/h (99 mph) do not seem to be true.

Initially they were used for all major expresses, but from 1943 they were replaced by the C38 Pacifics and used for less important services. In the fifties they received a Belpaire firebox and a new cab. From the late fifties, the C36 became more and more surplus due to the electrification of some lines and the introduction of diesel locomotives to other lines. The first one was withdrawn in 1959 and the last one in 1969.