To enable the replacement of Sydney's tramway system by buses, three batches of 'Underfloor' type buses were ordered by the Department of Government Transport (DGT). The first 100, Leyland OPSU1/1 Royal Tigers and AEC Regal IVs, were delivered in 1953 and 1954. This was followed by a further order for 250 buses.

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125 of this second order were Leyland ERT1/1 Royal Tiger Worldmasters. The Leyland chassis' were built in 1956 in the UK and shipped to Sydney, where Cycle Components Manufacturing Company (CCMC, later Custom Coaches) of Guildford, Sydney, built the bodies between 1957 and 1958. All were registered 2902 to 3131. The 125 remaining buses in the order were AEC Regal IVs, bodied by Commonwealth Engineering of Granville, and were registered 2882 to 3126. 

 

Finally, a third Underfloor order of 388 buses (206 Leyland and 182 AEC), was delivered from 1959 to 1961. These were bodied to a slightly different design by Commonwealth Engineering and Clyde Engineering. These buses were registered 3132 to 3519, with the Museum's AEC Regal IV Underfloor 3197 being representative of this final series.

 

3131 entered service in early 1959, initially from Enfield Depot where it ran Cabarita-Mortlake-Burwood-Ashfield services. Later being allocated to Brookvale, Willoughby, North Sydney, Burwood, Kingsgrove and Tempe Depots during its DGT career.

 

The bus was withdrawn from government service in 1983, by which stage it had been painted in the Public Transport Commission blue and white livery. 3131 was purchased for preservation by a group of enthusiasts, who had the bus returned to its original green and cream livery. 

 

Specifications:

Engine: Six cylinder Leyland 0.680 diesel, developing 150 b.h.p. at 2000 r.p.m., horizontal underfloor mount. 

 

Transmission: Four speed air operated pneumocyclic gearbox to a worm drive differential.

 

Brakes: Air operated foot brake and mechanical hand brake to the rear wheels.