The W class are a diesel-hydraulic shunting locomotive ordered and operated by the Victorian Railways of Australia.

In mid 1957, the Victorian Railways called for tenders for a fleet of 25 diesel-hydraulic locomotives rated at 500 hp (370 kW). Tulloch, based in Rhodes, New South Wales, won the contract with an offer for West German-style locomotives, using a Mercedes V12 diesel engine developing 660 hp (490 kW) which was coupled to a Krupp 2W1D46 hydraulic transmission powering the centre axle, with the leading and trailing axles powered via connecting rods. All 25 engines entered service in the year from December 1959.^[2]

Tulloch expected a repeat order for a further 25 units from the Victorian Railways, and also built a standard gauge version numbered 7101 as a demonstrator unit for the New South Wales Railways. However, the latter system rejected the design as unsuitable, so that unit was sold to the Victorian Railways and used for construction trains on the Albury NSW to Melbourne standard gauge line. After that project was completed, it became one of the standard gauge shunting units operating between South Dynon and Spencer Street station. The final engine, W267, had been built in anticipation of the repeat order that never eventuated - while the contract was written, it was never signed.^[3] Instead, the final engine was converted to standard gauge and shared duties with W266.

Engines were fitted with controls on both sides of the centre console, although that feature was removed not long after delivery.^[4][5] The engines were initially rostered on local passenger services to Werribee and trialled on Bacchus Marsh runs, but with the low speed limit of 40 mph (65 km/h) and relatively little power, they were unable to keep to the timetable to the latter.

The engines proved incredibly unpopular, due to problems with ride quality and engine reliability, and a transmission change needed to achieve mainline running speeds. The high gear setting was removed early on and the class relegated to shunting duties in an attempt to better utilise the fleet. However, the cab profile made visibility a problem in yards, and engine crews had to lean out the side to observe shunting instructions. The cab design also provided no shelter from the weather in storms or on hot days. Common failures included seized transmissions, oil leaking onto the shunters' steps creating a slip hazard, and failed engine blocks.^[6]

Between 1973 and 1977, at least ten engines, starting with W249,^[7] had the Mercedes engine removed and replaced with General Motors diesel units. Engines after the first had different exhaust arrangements, but all those refitted could be identified externally by a second exhaust stack at the end of the long hood, with the original adjacent to the driving cabin plated over.^[8] The alterations raised the engine hood by 208mm but did not replace the original transmission or gearbox.^[9]

The class was generally allocated to Ballarat, Geelong and Melbourne for short shunting trips, and one each at Ararat, Bendigo and Seymour, explicitly for yard work only. However, on the odd occasion, Seymour-based W241 was used on the Shepparton goods, and also ran out to Rushworth and Colbinabbin. It also made it to Benalla a few times.^[10]

The 71 class was a class of diesel locomotive operated by the New South Wales Department of Railways in Australia.

Table details are drawn from Newsrail, December 1982 p. 311.

• WAGR T class (diesel)