, the four-
axle Re 420 are mainly used for
freight services, where they are sometimes paired with the six-axle
Re 620 (Re 6/6), especially in mountainous regions. This pairing is referred to as
Re 10/10. Current freight operators using the Re 420 are
SBB Cargo and
Widmer Rail Service AG (WRS). Before the wide use of
electric multiple units, the Re 420 was frequently used for
passenger services, either as a single engine or in pairs. It is still in use for some passenger train services, for example for some peak-hour
commuter rail services of
Zurich S-Bahn, the
EuroCity Transalpin For these services, locomotives Re 4/4II 11103, 11106, 11108, 11109, 11112, 11113, 11133 and 11141 had to be adapted accordingly, as the wagons were delivered with automatic
couplings. The locomotives of the later series (from 11220, but without 11236–11238) were already prepared at the factory to accept the
UIC coupling. However, since these were not yet available at the time, some Re 420 locomotives had to be converted specifically for the Swiss Express. They received an extended shock beam, new couplings and the appropriate paint in the Swiss Express colors orange-stone gray-orange. They also bear the then newly introduced SBB logo (the Swiss cross with two arrows) instead of the typical
Swiss coat of arms on their fronts. The length over the
buffers was then instead of the usual . The automatic coupling protruded over the buffers, resulting in a total length of . With the adaptation of the
Einheitswagen III for shuttle train operation, the ends of the compositions were given normal screw couplings, and subsequently the locomotives too. On the occasion of major overhauls, locomotives № 11112, 11113 and 11133 were painted red; № 11103 and 11106 were taken over by the
BLS and painted in their typical silver-blue-green livery. The 11141 retained the Swiss Express livery and was parked at the beginning of October 2007 and has been used as a heating locomotive ever since. After a general inspection in Bellinzona, the engine has been back in use since autumn 2009 in the red livery of the series, but keeping the SBB logo at the fronts. It was later sold to DSF Koblenz which restored its original Swiss Express look. Locomotive 11108 has been parked since 25 September 2020 due to expired deadlines and is now in the
SBB Historic Depot in
Olten. Re 4/4II 11133 is an
ICN shunting locomotive in the
Yverdon-les-Bains main workshop and has an additional beam with automatic coupling on one side instead of the screw coupling and buffer. , locomotive 11109 (420 109-1) is the last one with the original Swiss Express scheme still in operation for passenger train services. Built in 1966, it is currently also the oldest operating Re 420 of Swiss Federal Railways.
Zurich S-Bahn (Re 420 LION) Between 2011 and 2016, 30 Re 420 locomotives of the passenger division (Re 4/4II 11201–11230) were refurbished for peak-hour services on the
Zurich S-Bahn network (renumbered Re 420 201–230). Each set is composed of six or ten
DPZ double-deck cars plus one
Re 420 LION locomotive at each end (head and tail configuration). The
acronym LION stands for
Lifting, Integration, Optimierung, Neugestaltung (in
German, ). These trainsets are currently in use as
S19,
S21 or
S23 services, among others.
Cross-border operations (Re 421) Six Re 4/4II (vehicle numbers 11196–11201; later 11195–11200) were equipped with a wider
pantograph wiper in order to conform with
Deutsche Bahn (DB) and
Austrian Federal Railways (ÖBB) standards, which subsequently allowed these units to pull
EuroCity (EC) trains over the borders to
Bregenz (Austria) and
Lindau (Germany). These workings were covered by the last series, engines 11371–11397, which were rebuilt for use in
Germany and
Austria, not only with a different pantograph but also with
PZB/Indusi and other systems necessary for use abroad. These locomotives are classified
Re 421 and are lettered for
SBB Cargo but they also pulled passenger trains to Bregenz and Lindau (however, 11382 was never converted as it was already withdrawn with fire damage). Some Re 421s were later bought by Widmer Rail Services AG (WRS). With the December 2020 timetable change, in conjunction with the reopening of
Lindau-Reutin station and
electrification of the
line to Munich, services between and
Munich Central Station were no longer hauled by locomotives, but instead
New Pendolino EMUs of SBB started operations on this line as EC/
ECE. ==Re 430 subseries==