When the VR required a light shunting and goods loco in the early 60's they decided on the Clyde tender for a 448 kW G6B.
To cut costs the VR supplied the bogies, which were salvaged power bogies from redundant electric suburban M cars.
The contract was signed in December 1962 for twenty five locomotives.
These locos were delivered from September 1963. Although acquired mainly for shunting duties, they were used on commuter services and freight trains.
A second batch was ordered in the mid 60's with minor improvements.
This boosted the number of units to 50, replacing the remaining steam locos for country shunting duties.
Between December 1967 and August 1968 25 additional units were acquired, but this final batch were equipped with the EMD 645E engine.
Withdrawals commenced in 1985 and large scale scrappings took place during 1991 and 92.
Less than half the class are still in service with most now being found in major regional centres and Melbourne.
Y133 is allocated to the Seymour Railway Heritage Centre and Y164 is allocated to Steamrail.
The Central Highlands Tourist Railway acquired Y159 and it is preserved in operating condition.