Quite a few of the Australian state railroads acquired locomotives of around 1000 hp for secondary and branch line duties in the 1950s and 1960s, and the VR T class fell into this group. New South Wales (NSWGR), South Australia (SAR) and Queensland (QR) all opted for light-axle load six-axle locomotives, to enable their use on lightly-laid branch lines, whereas VR chose four axles. Collectively, this group of locomotives was often referred to as the branch line type, to distinguish it from the more powerful main line group. The branch line locomotives were equipped for road service, with road-type brakes (A7EL or B7EL) and MU, but not dynamic brakes.
The most common branch line type was the Alco DL531, operated by NSWGR and SAR, pertinent here because some of that fleet were fitted with GE electrical equipment, either full or partial sets. Otherwise, GE’s only other participation was in the first group of QR branch line locomotives, which were GE 70 tonner derivatives, and less powerful than the bulk of the branch line fleet.
Below that level, in the realm of switching and transfer locomotives, there was more diversity, including the use of locally built Walkers B-B diesel-hydraulic locomotives. (Which despite their “disadvantaged” start in life as derivatives of an NBL design, apparently performed satisfactorily.) The VR Y was equipped to MU with its larger brethren, but on the other hand had a simple braking system with a #4 automatic brake valve and a Type W self-lapping independent brake valve, the independent not being trainlined. On the other hand, perhaps by circumstance, it had swing bolster trucks, which with their MU car origins, may well have ridden and tracked better at higher speeds than the flexicoil trucks under the T class. On the other hand, the SAR’s home-built 500 class, generally similar to the Y albeit a little lighter and less powerful, had rigid bolster trucks, was not fitted for MU, but had A7EL brakes to cover any main line use.