The reference for locomotives and railcars
MPI MPXpress
United States | 2003 | 243 produced
Caltrain MP36PH-3C No. 927 in October 2018 at South San Francisco station
Caltrain MP36PH-3C No. 927 in October 2018 at South San Francisco station
aqua scissors

Motive Power, Inc., as the successor company to Morrison-Knudsen or MK Rail, offered a range of passenger diesel locomotives from 2003 that were intended for commuter service. These were four-axle diesel-electric locomotives with a streamlined head shape on one end. Initially, power was provided by the sixteen-cylinder two-stroke engine from the 645 series from EMD with 3,600 hp

The first two models were the MP36PH-3S and MP36PH-3C. With the 3S, the power supply for the passenger cars was provided by a static inverter, which made it necessary for the diesel engine to run constantly at nominal speed to provide the required frequency. When calling up the maximum 500 kW, the power available to the traction motors was reduced by this value. The 3C used an additional Caterpillar C27, which provided power for the train independently of the main diesel. From 2015, all Type 3S engines have been upgraded to the same level as the 3C to reduce stationary noise and fuel consumption.

SunRail MP32PH-Q in October 2016 at the Sand Lake Road station
SunRail MP32PH-Q in October 2016 at the Sand Lake Road station

From 2007 the MP40PH-3C was delivered, which got a newer EMD engine of the 710 series, which provided 4,000 hp. Here, too, an additional diesel engine was used to supply the train. From 2013 the MP32PH-Q was manufactured, which resulted from the conversion of existing EMD GP40WH-2 and differs from the other models in that the hoods around the prime mover were unchanged and only the head got a new shape. Despite the 32 in the name, the existing engines were upgraded from 3,000 to 3,600 hp

Since the new registration of locomotives with the EMD two-stroke engine was no longer possible with the EPA Tier 4 emissions standard coming into effect in the USA on January 1, 2015, production of the locomotives with these engines ended. Now MPI offered the MP54AC with two 2,700 hp Cummins QSK60, which meet the new emissions standard and have an AC drive system. To reduce fuel consumption and emissions, one of the engines can be switched off as needed, making the MP54AC a genset loco.

The largest number is made up of the MP36PH-3C, of which just over 100 were built. It went to a total of nine commuter companies in the USA. Twenty-seven examples of the similar -3S were built for Metra in the Chicago area. Of the MP40PH-3C, most of the 71 examples went to the Canadian GO Transit, as did all 26 examples of the MP54AC. The first MP54AC was created by converting a GO Transit MP40PH-3C accordingly. Only eleven examples of the MP32PH-Q were built for SunRail in the Orlando, Florida area. Most of these had been converted from former MARC (Maryland Area Rail Commuter) GP40WH-2s.

VariantMP32PH-QMP36PH-3S and -3CMP40PH-3CMP54AC
Built2013-20142003-20142007-2014since 2015
Axle configB-B 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length68 ft 0 in
Fixed wheelbase9 ft9 ft 4 in
Service weight285,000 lbs295,000 lbs
Adhesive weight285,000 lbs295,000 lbs
Axle load71,250 lbs73,750 lbs
Power sourcediesel-electric
Top speed102 mph93 mph110 mph
Starting effort70,000 lbf72,500 lbf85,000 lbf82,900 lbf
EngineEMD 16-645E3CEMD 16-645F3BEMD 16-710G3B-T2Cummins QSK60
Engine typeV16 diesel2x V16 diesel
Engine output3,600 hp (2,685 kW)4,000 hp (2,983 kW)5,400 hp (4,027 kW)
Power Plant
Calculated Values
diesel locomotive
three-phase AC
last changed: 09/2022

We use cookies to save the following settings:

  • selected navigation structure
  • selected language
  • preferred units
  • spelling of railway company names

If you refuse the use of cookies, the settings will only be retained for the current session and will be reset to the default values the next time you visit the site.

Display of units

Here you can set the desired unit system for the technical data.

  • Metric: Lengths in meters, weights in tonnes, and volumes in cubic meters
  • Imperial (UK): Lengths in feet/inches, weights in long tons and volumes in imperial gallons
  • Imperial (US): Lengths in feet/inches, weights in pounds, and volumes in US gallons
  • Individual: Depends on the country of origin of each locomotive
Operator names

Here you can set the display of railway company names.

  • Short: Abbreviation or short form of the name
  • Standard: commonly used name, partially translated to English
  • Complete: full name in local language