In 1980 and 1981, the South African Railways placed thirty Class 34–900 General Electric type U26C diesel-electric locomotives in service.

The ex Iscor Class 34-500 loco­motives could be visually dis­ting­uished from the other series by the air conditioning units mounted on the cab roofs of most of them and initially, when it was still a feature unique to them, by their running board-mounted handrails.

[5] At some stage during the mid-1980s, all Class 34-000, 34-400 and 34-500 locomotives had saddle filters installed across the long hood, mounted just to the rear of the screens on the sides behind the cab.

[6] To be usable on the iron ore line, Class 34-900 locomotives which ended up working there were modified to a similar fuel capacity.

[7] Class 34-900 locomotives which are allocated to the Sishen-Saldanha Orex line are usually further modified by having removable running board-mounted handrails installed.

In the 1990s many of the Class 34-900 units began to be repainted in the Spoornet orange livery with a yellow and blue chevron pattern on the buffer beams.