At the same time that the SBB was procuring a modern bogie electric locomotive, the Re 4/4^I, the Rhaetian Railway also ordered four similar machines in a smaller version. As with the Re 4/4^I, the mechanical part came from the SLM and the electrical system from BBC and Oerlikon. They were the first RhB electric locomotives without a rod drive and, with an initial top speed of 75 km/h, were mainly intended for express trains. Since the first locomotives proved their worth, a further six were purchased in 1953. The maximum towing capacity at 3.5 percent was 185 tonnes and at 4.5 percent 135 tonnes.

The heavier Ge 6/6^I that appeared a few years later already contested parts of its area of responsibility. At the latest, the Ge 4/4^II built from 1973 pushed the Ge 4/4^I out of service with express trains. However, since they were also suitable for use in front of freight trains, they could remain in service for a long time. From 1986 they were modernized, receiving more spacious cabs with a more modern head shape, single-arm pantographs and multiple and push-pull train controls. In the meantime it had been certified for 80 km/h.

No. 608 still with historic head shape in 1985

Alain Gavillet / Trams aux fils

Since the 1990s, they have mainly been used in front of freight trains and push-pull trains. Between November 2010 and May 2011, six of the ten examples were scrapped. In 2018, however, the remaining four were still in service, including number 602 after a three-and-a-half year stay at the Lucerne Museum of Transport. The number 603 is to be handed over to the Augsburg Railway Park and some of the others are even being used in front of the Glacier Express.

As a replacement for the Ge 6/6^I “Crocodiles”, the RhB received a total of 23 Ge 4/4^II in two batches in 1973 and 1984. The locomotives already had electronically controlled rectifiers, multiple controls and they can be used together with control cars. On a gradient of 4.5 percent, 185 tonnes can be pulled by one locomotive. From 2004 they were equipped with computer-controlled control electronics. After a second modernization from 2016, they will remain in use for a few more years and can also transport the modern Alvra articulated trains.