|In EMT days 158 770 at Derby|
|Number built:||354 (182 2 and 3 car sets)|
|Engine:||Cummins NTA855R1/3 or Perkins 2006-TWH diesel engine per power car|
|Power:||350 hp (260 kW) or 400 hp (300kW) per vehicle|
|Formation:||2-car : Driving Motor Standard Lavatory (DMSL)+DMSL
or DMSL+Driving Motor Composite Lavatory (DMCL)
3-car : DMSL+Motor Standard (MS)+DMSL
The Class 158 operates as either a 2 or 3-car set, mostly with a Cummins engine though a few were fitted with Perkins engines instead. Currently the fleet is split into the 158/0 and 158/9 sub-classes. The latter were originally 2-car sets but were beefed up into 3-car by the addition of an extra driving coach though the cab of this is locked out of use.
The Class 158 is in operation with Northern, Scot Rail, Transport for Wales, South Western Railway, Great Western Railway and East Midland Railway (formerly East Midland Trains). Twelve 3-car sets were also built by BREL Derby for the Thailand state railway and also continue in service.
|Northern 158 787 at York|
|Transport for Wales 158 825 at Cardiff Central|
|Back in Arriva Trains Wales days 158 826 passes through Smethwick Rolfe Street|
|EMT 158 854 approaches Duffield|
|EMT 158 856 at Sheffield|
 Colin J Marsden, DMU and EMU Recognition Guide (Ian Allan, 2013) p. 140