General Electric has been offering the U20C since 1964, which was primarily intended for use in developing countries with its low axle load and suitability for a wide variety of track gauges. According to GE's scheme, the model designation stands for the Universal Series, an output of 2,000 hp and three axles per bogie. To achieve the required power at low weight, the 7FDL with eight cylinders and two turbochargers was used. On request, the engine could also be ordered with twelve cylinders. The locomotive could be built for gauges between three feet (914 mm) and the Indian broad gauge with 1,676 mm.

The more than 1,000 machines were built in the USA, Brazil, Indonesia, South Africa and Germany. Several hundred were delivered to Brazil with a gauge of 1,000 or 1,600 mm. Several hundred also went to African customers. The largest numbers came to South Africa with 190, 114 to Mozambique and 83 to Zambia. Others went to Pakistan, Argentina, Bolivia, Colombia, Jordan and Turkey.

The U20C of the Indonesian KAI have a special position. They received a cab with a wide nose and slanted front end, manufactured by UGL Rail in Australia. The first twelve CC203 were delivered to Indonesia by GE from the USA starting in 1995 and 29 more were built directly by PT GE Lokomotif Indonesia. A locomotive was built for the Philippines in 2000 and has been in service in Australia since 2007. From 2006 followed 30 CC204, which are designated by GE as C20EMP and have a 2,150 hp engine with computer-aided control.

Chilean operator SQM's U20C in April 2012 with a nitrate train at Barriles

Kabelleger / David Gubler

In Indonesia, the locomotives were initially used mainly for express trains of the “Argo” brand. With the introduction of newer locomotives, they were increasingly used in front of local and freight trains. Six belong to a private operator and haul pulp trains. Four CC203s have now been retired. Since the introduction of the CC206, the CC204 has also increasingly had to pull freight trains.