In the early eighties V/Line upgraded its passenger services with comfortable air-conditioned passenger cars and fast express locomotives. As new locomotives were expensive, V/Line decided to re-build and heavily modify the twenty six ageing B class locomotives. While the basic shape of the B class was retained, just about everything else was modernised. This included fitting a 645E3B series engine, improved alternator packages, better crew facilities (including air-conditioning) and many other modifications. The first locomotive modified was B73, which had suffered and electrical fire. It emerged as A73 in December 1983 from Clyde's Rosewater plant in South Australia. During the rebuild there had been several problems trying to fit the new technology into the old frames but these were overcome.

   Although the rebuild was a technical success, the Victorian Government abandoned the project after eleven units had been modified. The cost of modifying the B class compared to the purchase of a new locomotive was seen to be too small. As a result of this, twenty five N class express passenger locomotives were built between August 1985 and July 1987.

   With the splitting and privatisation of V/Line into V/Line Freight (now Freight Victoria) and V/Line Passenger, the A class were split up between the two operators. Some are now used exclusively for freight while others are used exclusively for passenger services.