|Builder:||Birmingham Railway Carriage & Wagon Company|
|Engine:||Sulzer 6LDA28B diesel|
|Power:||1, 250 hp (932 kW)|
The original locomotives were the 27/0, two sub-classes were later modified for express services in Scotland. Some locomotives were modified for push-pull operations as the 27/1 and some with electric train heat as the 27/2. One of each top and tailed Edinburgh-Glasgow expresses in the 1970s however their reliability suffered on these duties, a number of 27/2s catching fire. By the end of the decade they had been replaced by Class 47/7s. The Class 27s were gradually withdrawn throughout the 1980s with the final withdrawals in 1987 however 8 have been preserved.
|D5410 at Kidderminster|
 Brian Haresnape, Production Diesel-Electrics Types 1-3 (Ian Allan, 1983) p. 40
 Chris Heaps, BR Diary 1968-1977 (Ian Allan, 1988) p. 45
 John Glover, BR Diary 1978-1985 (Ian Allan, 1985) p. 27