British Rail Class 142

British Rail Class 142 Pacer
In service	1985–
Manufacturer	BREL Derby and Leyland Bus
Built at	Derby
Family name	Pacer
Constructed	1985–1987
Refurbishment	1997–2003
Number built	96
Number in service	94
Number scrapped	2
Formation	2 cars per trainset
Fleet numbers	142001–142096
Capacity	102 to 121 seats per trainset
Operator(s)	Arriva Trains Wales First Great Western Northern Rail
Line(s) served	Cheshire, Greater Manchester, Lancashire, Merseyside, Teeside,Tyne & Wear, Valley Lines, Yorkshire
Specifications
Car body construction	Steel
Articulated sections	Flexible diaphragm within unit only
Maximum speed	75 mph (120 km/h)
Weight	48.23 t (47.47 long tons; 53.16 short tons) per trainset
Prime mover(s)	Cummins LTA10-R (Originally Leyland TL11)
Safety system(s)	AWS, TPWS
Track gauge	1435 mm (4 ft 8½ in)

142086 at Colne on 28 December 2005 forming a Northern Rail service to Blackpool South

Distinctive roof of Class 142 at Leeds. 1 July 2006

The British Rail Class 142 is a class of Pacer diesel multiple units used in the United Kingdom. 96 units were built by BREL in Derby between 1985 and 1987. They were a development of the earlier Class 141 which were introduced in 1984.