British Rail Class 25

British Rail Class 25
Class 25 locomotive stands on Springs Branch Traction Maintenance Depot at Wigan
Power type	Diesel-electric
Builder	British Railways’ Crewe Works, Darlington Works and Derby Works; Beyer, Peacock & Co.
Build date	1961–1967
Total production	327
Configuration	Bo-Bo
UIC classification	Bo'Bo'
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter	3 ft 9 in (1.143 m)
Minimum curve	4.5 chains (91 m)
Wheelbase	36 ft 6 in (11.125 m)
Length	50 ft 6 in (15.392 m)
Width	9 ft 1 in (2.769 m)
Height	12 ft 8 in (3.861 m)
Locomotive weight	71 long tons (72.1 t) to 76 long tons (77.2 t)
Fuel capacity	500 imp gal (2,300 l; 600 US gal)
Prime mover	Sulzer 6LDA28-B
Transmission	DC generator, DC traction motors
Multiple working	★ Blue Star
Top speed	90 mph (145 km/h)
Power output	Engine: 1,250 hp (932 kW)
Tractive effort	Maximum: 39,000 lbf (173,000 N) to 45,000 lbf (200,000 N)
Train heating	Steam
Locomotive brakeforce	38 LTf (380 kN)
Train brakes	Vacuum
Career	British Railways
Number	D5151–D5299, D7500–D7677; later 25001–25327
Nicknames	Rats
Axle load class	Route availability 4

The British Rail Class 25 diesel locomotives were also known as Sulzer Type 2 and nicknamed Rats. 327 locomotives of this type were built between 1961 and 1967.