The 42 class were a class of Australian diesel locomotives built by Clyde Engineering, Granville for the New South Wales Government Railways between November 1955 and December 1956.
The design was based on the General Motors EMD F7 locomotive and they were very similar to the GM12 class then being built by Clyde Engineering for the Commonwealth Railways. They initially worked express passenger services including the Brisbane Limited and Melbourne Limited and later the Intercapital Daylight, Southern Aurora and Spirit of Progress. As newer locomotives arrived they were concentrated on the Main South line operating freight services. By the late 1970s the Australian Federated Union of Enginemen had placed a ban on the 42 class operating as lead engines due to cab conditions. In 1980 4201 had its cab upgraded during overhaul to overcome these issues but with their replacement imminent it was decided not to treat the rest of the class. All were withdrawn in 1983. Three have been preserved:
- 4201 was acquired by the New South Wales Rail Transport Museum. It has been used extensively on charters across the state and ventured interstate to Melbourne. It retains the green and yellow livery it received for the 125th anniversary of NSW railways. As at December 2012 it was undergoing repairs at Maintrain, Auburn.
- 4204 was acquired by the Lachlan Valley Railway, After being restored by apprentices at Clyde Engineering, Kelso in 1986 to the same as when it was built, it has been used extensively on charters across the state and on freight services by Lachlan Valley Rail Freight. As at December 2012 it was often hired to Southern Shorthaul Railroad for use on infrastructure trains in New South Wales and Victoria.
- 4206 was acquired by the Dorrigo Steam Railway and Museum. After being used extensively on the Dorrigo line hauling infrastructure and stock trains from Glenreagh, it was withdrawn when the line closed.
|Locomotive||Serial No||Entered Service||Current Owner||Livery||Status|
|4201||55-74||Nov 55||Rail Transport Museum||Green & yellow||Repairs, Maintrain|
|4203||55-79||Jan 56||O'Donohugue's Pub||-||Emu Plains|
|4204||56-87||Mar 56||Lachlan Valley Railway||Indian red||Operational|
|4206||56-100||Aug 56||Dorrigo Steam Railway & Museum||Indian red||Stored|