|Number built:||56 (23 2 and 3-car sets)|
|Builder:||BREL Derby & Walter Alexander|
|Engine:||Cummins LTA10-R diesel per car|
|Power:||450/675 hp (330/495 kW)|
|Formation:||(2-car) Driving Motor Standard (DMS)+
Driving Motor Standard Lavatory (DMSL)
(3-car) DMS+Motor Standard (MS)+DMSL
The Class 144 was ordered for services in West Yorkshire . To cope with an increase in passengers West Yorkshire PTE later ordered 10 extra Motor Standard trailers to augment ten trains to 3-cars. These are the only vehicles in the large Pacer fleet to have no driving cabs. The Class 144 was originally built with Leyland TL11 engines but these were later replaced by Cummins diesels. The original transmission has also been replaced with a Voith diesel-hydraulic system .
As with the rest of the Pacer fleet the Class 144s face withdrawal by 2020. One Class 144 has been modified as the Class 144e (for Evolution) to meet future accessibility standards with an accessible toilet and a new interior/seating  however no others have been modified to to 144e standard and replacement stock has instead been ordered. All are currently operated by Northern.
|Northern 144 008 at Sheffield|
|Three car 144 020 at York|
|Northern 144 013 at Sheffield|
|Pacer front end comparison: Northern 142 023 and 144 020 at York|
|Northern 144 017 at Sheffield|
 Colin J. Marsden, DMU and EMU Recognition Guide (Ian Allan, 2013) p. 127
 Colin J. Marsden, Rail Guide 2016 (Ian Allan, 2016) p. 91