SBB Bm 4/4

SBB-CFF-FFS Bm 4/4
Bm 4/4 18439 at Lausanne train station
Type and origin Power type Diesel Builder SLM, SAAS Build date 1960–1970 Total produced 46
Specifications Configuration: ​  • AAR B-B  • UIC Bo′Bo′ Gauge 1,435 mm (4 ft 8+1⁄2 in) Length 12,650–13,710 mm (41 ft 6 in – 45 ft 0 in) Loco weight 72 tonnes (70.9 long tons; 79.4 short tons) Traction motors Four Transmission Diesel electric
Performance figures Maximum speed 75 km/h (47 mph) Power output 620kw (840hp)
Career Operators SBB-CFF-FFS Numbers 18401–18446 Withdrawn From 2006

The Bm 4/4 is a class of heavy diesel shunting locomotives built for Swiss Federal Railways. 46 examples were built between 1960 and 1970, numbered 18401 to 18446, Starting in 2006, the class was slowly being replaced by new Vossloh-built locomotives. The last SBB example was withdrawn in 2024 but a few are in use with private operators

See also

• List of stock used by Swiss Federal Railways