British Rail Class 108

British Rail Class 108
Class 108 DMU, nos. 50980 and 52054, at Bodmin on 28 August 2003. This unit is preserved on the Bodmin & Wenford Railway in Cornwall.
Driver's cab, with the signal token in the middle
In service	1958–1990
Manufacturer	British Railways
Built at	Derby Works
Constructed	1958–1961
Number built	DMBS: 152, DMCL: 58, DTCL: 106, TSL: 11, TBSL: 6. Total: 333 cars
Formation	2, 3, or 4-car sets
Capacity	DMBS: 52 second class, DMCL: 12 first 53 second, DTCL: 12 first 53 second, TSL: 68 second class, TBSL: 50 second class
Operator(s)	British Rail
Specifications
Car length	58 ft 1 in (17.70 m)
Width	9 ft 3 in (2.82 m)
Height	12 ft 4 in (3.76 m)
Maximum speed	70 mph (113 km/h)
Weight	Power cars: 29.5 tonnes (29.0 long tons; 32.5 short tons), Trailer cars: 21.5 to 23.5 tonnes (21.2 to 23.1 long tons; 23.7 to 25.9 short tons)
Prime mover(s)	Two BUT (AEC) then BUT (Leyland)
Power output	150 bhp (110 kW) per engine
Transmission	Mechanical: 4-speed epicyclic gearbox
Safety system(s)	AWS
Multiple working	■ Blue Square
Track gauge	4 ft 8 1⁄2 in (1,435 mm)

The British Rail Class 108 diesel multiple units were built by BR Derby from 1958 to 1961, with a final production quantity of 333 vehicles.

These units stayed in regular service until 1990, when they began to be withdrawn from traffic. They were replaced on regional services by the new "Sprinter" derivative units, or by "Turbo" units on services around London. The final units lasted in traffic until October 1993, although many saw further use in departmental service, as sandite or route-learner units. Good condition on withdrawal and lack of asbestos has ensured that many of this class are now used on preserved railway lines.

Many vehicles have been preserved on heritage railways. None are currently certified for use on the main line - although the Swanage Railway's set was hauled from the railway to Eastleigh and back, for overhaul - and is believed to be the first class 108 to have been seen on main lines for a very long time.