View source for MPI MPXpress

{{short description |Line of diesel-electric passenger locomotives}}
{{more citations needed|date=August 2016}}
{{Infobox locomotive
| name = MPI MPXpress
| image = Trainroadrunner.jpg
| caption = MP36PH-3C of [[New Mexico Rail Runner Express]] 
| powertype = [[Diesel-electric]]
| builder = [[MotivePower]]
| builddate = {{Start date|2003}}–{{End date|2024}}
| totalproduction = 237
*MP36PH-3S: 27
*MP36PH-3C: 103
*MP40PH-3C: 70
*MP32PH-Q: 11
*MP54AC: 26
| numberrebuilt = {{Unbulleted list
   | MP36PH-3S: 27 (to MP36PH-3C)
   | MP40PH-3C: 1 (to MP54AC)
   }}
| aarwheels = B-B
| uicclass = Bo'Bo'
| gauge = {{track gauge|ussg|allk=on}}
| wheeldiameter = {{convert|3|ft|4|in|mm|abbr=on}}
| minimumcurve = {{convert|248|ft|mm|abbr=on}}
| wheelbase = {{Unbulleted list
   | {{convert|9|ft|0|in|mm|abbr=on}} (original)
   | {{convert|9|ft|4|in|mm|abbr=on}} (new)
   }}
| length = {{convert|68|ft|m|2|abbr=on}}
| width = {{convert|10|ft|7.5|in|mm|abbr=on}}
| height = {{convert|15|ft|6|in|mm|abbr=on}}
| locoweight = {{convert|285000|to|295000|lb|kg|abbr=on}}
| primemover = {{Unbulleted list
   | [[EMD 645|EMD 16-645F3B]] (MP36PH-3S, MP36PH-3C)
   | [[EMD 710|EMD 16-710G3B-T2]] (MP40PH-3C)
   | [[EMD 645|EMD 16-645E3C]] (MP32PH-Q)
   | (2x) [[Cummins]] QSK60 (MP54AC)
   }}
| maxspeed = {{Unbulleted list
   | {{convert|82|-|102|mph|km/h|abbr=on}} (MP36PH-3C, MP32PH-Q)
   | {{convert|93|mph|km/h|abbr=on}} (MP40PH-3C)
   | {{convert|110|mph|km/h|abbr=on}} (MP54AC)
   }}
| poweroutput = {{Unbulleted list
   | {{convert|3600|hp|kW|abbr=on}} (MP36PH-3S, MP36PH-3C)
   | {{convert|4000|hp|kW|abbr=on}} (MP40PH-3C)
   | {{convert|5400|hp|kW|abbr=on}} (MP54AC)
   | {{convert|3200|hp|kW|abbr=on}} (MP32PH-Q)

   }}
| tractiveeffort = {{Unbulleted list
   | {{convert|72500|-|85000|lbf|kN|abbr=on}} (MP36PH-3C, MP36PH-3S)
   | {{convert|85000|lbf|kN|abbr=on}} (MP40PH-3C)<ref>{{cite web | url=http://libraryarchives.metro.net/DPGTL/studies/2009-DMU-technology-investigation.pdf | title=LOS ANGELES COUNTY METROPOLITAN TRANSPORTATION AUTHORITY: Diesel Multiple Unit (DMU) Technical Feasibility Analysis | work=LTK Engineering Services | date=May 4, 2009 | access-date=September 7, 2014}}</ref>
   | {{convert|70000|lbf|kN|abbr=on}} (MP32PH-Q)
   | {{convert|82900|lbf|kN|abbr=on}} (MP54AC)
   }}
| operator = [[MPI MPXpress#Operators|See list]]
}}
The '''MPI MPXpress''' is a line of [[diesel locomotive#diesel-electric|diesel-electric locomotives]] built by [[MotivePower]] (a subsidiary of [[Wabtec]]) for [[commuter rail]] service. There are five MPXpress models: '''MP36PH-3S''', '''MP36PH-3C''', '''MP40PH-3C''', '''MP32PH-Q''', and '''MP54AC'''.

MPXpress locomotives were built with a high percentage of [[Remanufacturing|re-manufactured parts]] including diesel engines, major electrical components, trucks, and frames. Cabs, fuel tanks, electronics, HEP package, and other replaceable parts such as wheels and couplers were new when delivered. The re-manufactured components kept the price of locomotives down while providing like-new components with full warranty protection.<ref>{{Cite web |date=2020 |title=Metrolink Rail Fleet Management Report |url=https://metrolinktrains.com/globalassets/about/agency/sustainability/reports/metrolink-rail-fleet-management-plan-update---full-report.pdf |access-date=November 21, 2023 |website=[[Metrolink (California)|Metrolink]] |page=32}}</ref> The new cabs also made the MPXpress the first production passenger locomotive that met U.S. federal [[crashworthiness]] requirements.

The MPXpress line has kept pace with increasingly stringent [[United States Environmental Protection Agency|EPA]] locomotive emissions regulations, having provided the first—and in some cases, only—passenger locomotive for each of the four emission levels (tiers) that were specified by the EPA between 2002 and 2015.

The MPXpress is used by numerous public transit agencies in [[Canada]] and the [[United States]]; of them, [[GO Transit]] has the most, with 93 in their fleet.

{{As of |2023}}, Wabtec no longer lists the MPXpress in its locomotive portfolio.<ref>{{cite web |url=https://www.wabteccorp.com/locomotive |title=Locomotive Equipment |publisher=[[Wabtec]] |access-date=2023-04-17}}</ref>

== Models ==

=== MP36PH-3S ===
[[File:Metra 408.jpg|thumb|A [[Metra]] MP36PH-3S in [[Blue Island–Vermont Street station|Blue Island]]. [[Metra]] is the only railroad that ordered this model.]]
The MP36PH-3S used a 16-cylinder [[EMD 645]]F3B diesel engine as its [[Prime mover (locomotive)|prime mover]], capable of generating 3,600 [[Horsepower|hp]]. [[Head-end power]] (HEP) was generated by a static inverter that received its power through connections to the prime mover (hence the "S" (static) designation). Compared to a locomotive with a separate HEP generator, the prime mover had to constantly maintain a higher [[Revolutions per minute|RPM]] in order to supply power to the passenger cars. The setup was simpler but led to higher noise levels and higher fuel consumption.

When providing the maximum 500&nbsp;kW HEP load, maximum traction power is reduced to 2,930&nbsp;hp since HEP generation diverts some power from the prime mover.<ref>{{cite web|url=http://www.ltk.com/projectexperiencedetails.aspx?SPN=LOCOMOTIVES |title=Locomotives |work=LTK Engineering Services |archive-url=https://web.archive.org/web/20160304041502/http://www.ltk.com/projectexperiencedetails.aspx?SPN=LOCOMOTIVES |archive-date=March 4, 2016 |url-status=dead }}</ref>

The MP36PH-3S was the first variety of MPXpress locomotive to be built and the launch customer was [[Metra]], a commuter railroad in the [[Chicago]] area. Metra ordered 27 of these locomotives in 2001, which were built and delivered between 2003 and 2004. Fourteen were to replace the railroad's aged [[EMD F40C|F40C]] fleet, while the rest were for fleet expansion. Until May of 2020, when the 3S variants were converted to 3C's, Metra was the only operator of the MP36PH-3S variant of the MPXpress.

When the locomotives were first delivered, the onboard computer systems proved problematic. At one point in 2004, because Metra had so many MPXpress locomotives out of service, two F40Cs had to be placed back into service for a short time.

==== Conversion to MP36PH-3C specification ====
Starting in 2015, Metra began converting its MP36PH-3S locomotives to the MP36PH-3C specification by removing the static inverter and replacing it with a separate HEP generator. Metra's MP36PH-3C locomotives all have extended radiators to supply the extra cooling for the new Caterpillar generators. Locomotive No. 417 was the first one to be converted and was sent to MPI in Boise. The rest were rebuilt at Metra's 47th Street shops on the South Side of Chicago. As of 2020, all of the MP36PH-3S locomotives have been converted to the MP36PH-3C specification.

=== MP36PH-3C ===
[[File:Caltrain JPBX 927 at Palo Alto station.JPG|thumb|An MP36PH-3C in [[Caltrain]] livery. Nine railroads operate this model, with [[Caltrain]] being the launch customer.]]
The MP36PH-3C has the same EMD 645F3B prime mover as the MP36PH-3S model, but with a separate head-end power generator, a [[Caterpillar Inc.|Caterpillar]] [[Caterpillar C27|C-27]] (3412 before 2005).<ref name="Bob Lex2">{{cite journal|last=Lex|first=Robert|date=29 September 2013|title=Northstar Commuter Rail MP36PH-3C Parts|journal=Parts List for MPXpress Locomotives}}</ref>

The launch customer for the MP36PH-3C was [[Caltrain]], a commuter railroad in the [[San Francisco Bay Area]]. Caltrain ordered 6 of these locomotives in 2003, which were built and delivered that same year. This locomotive has gone on to become the most popular MPXpress variant, with 100 delivered to nine different customers.

=== MP40PH-3C ===
[[File:GO locomotive 623 outside Union Station.jpg|thumb|An MP40PH-3C in the old [[GO Transit]] livery. [[GO Transit]] and [[Sounder commuter rail|Sounder Commuter Rail]] operate this model.]]
The MP40PH-3C introduced a new prime mover, the larger 16-cylinder [[EMD 710]]G3B series diesel engine, capable of generating 4,000&nbsp;hp. The MP40PH-3C also uses an EMD alternator and traction motors.

The launch customer for the MP40PH-3C was [[GO Transit]], a commuter railroad in the GTHA (Greater Toronto and Hamilton Area). The MP40PH-3C was developed in response to a bid request from GO Transit for locomotives capable of generating 4,000&nbsp;hp, hauling 12 passenger cars and traveling at speeds up to {{convert|93|mph|km/h|abbr=on}}. MotivePower and GE Transportation responded to the request, with MotivePower being selected as the winning bidder. GO Transit placed an order for 27 locomotives in 2006, which were built and delivered between 2007 and 2008.

In 2011, MotivePower upgraded the MP40PH-3C to comply with the EPA's more stringent Tier 3 emissions standard,<ref name="sunrail" /><ref>{{cite web|url=http://www.wabtec.com/upload/pressrelease/09.08.11%20-%20MPI%20Locomotive%20Orders.pdf|title=Archived copy|access-date=November 3, 2011|url-status=dead|archive-url=https://web.archive.org/web/20120415135806/http://www.wabtec.com/upload/pressrelease/09.08.11%20-%20MPI%20Locomotive%20Orders.pdf|archive-date=April 15, 2012}}</ref> which was in effect between 2012 and 2014. Three locomotives meeting this standard were built, all delivered to [[Sounder commuter rail]] in the [[Seattle]] area. Ten additional locomotives for GO Transit are also Tier 3 compliant.

=== MP32PH-Q ===
[[File:SunRail train leaving Winter Park Station.JPG|thumb|An MPI MP32PH-Q locomotive in [[SunRail]] livery. [[SunRail|Sunrail]] is the only operator of the MP32PH-Q.]]
The MP32PH-Q was built from 2013 to 2017 for [[SunRail]]. They have similar specifications as new MPXpress locomotives, but are rebuilt and refurbished from units that had previously operated on [[MARC Train|MARC]] as [[EMD GP40-based passenger locomotives#GP40WH-2|GP40WH-2]] locomotives. Inside the locomotive, the [[EMD 645|EMD 16-645E3C]] prime mover has been rebuilt and is rated at 3,200 horsepower.<ref> {{cite web |title=Science of SunRail |url=https://scienceofsunrail.com/mechanical/#:~:text=SunRail%20locomotives%20are%20an%20impressive,into%20a%20usable%20electric%20current. |publisher=SunRail |access-date=2025-05-04}}</ref> Electronics were upgraded using similar systems to those found on other MPXpress locomotives. On the exterior, the MP32PH-Q retains the [[hood unit]] layout of the former GP40WH-2, but a new four-window MPXpress cab replaces the original cab.<ref name="sunrail">{{cite journal | url=http://trn.trains.com/en/Railroad%20News/News%20Wire/2011/09/SunRail%20Sound%20Transit%20order%20MotivePower%20locomotives.aspx | title=SunRail, Sound Transit order MotivePower locomotives | date=September 12, 2011 | access-date=September 13, 2011 | journal=[[Trains (magazine)|Trains]] | archive-date=September 20, 2012 | archive-url=https://web.archive.org/web/20120920014216/http://trn.trains.com/en/Railroad%20News/News%20Wire/2011/09/SunRail%20Sound%20Transit%20order%20MotivePower%20locomotives.aspx | url-status=dead }}</ref><ref name="tf201404">{{cite journal|url=http://www.cfrhs.org/Flatwheel/2014/April%202014.pdf |title=Winter Park's Station Dedication |author=Murdock, Ken |journal=The Flatwheel |date=April 2014 |volume=3-5 |archive-url=https://web.archive.org/web/20140908044501/http://www.cfrhs.org/Flatwheel/2014/April%202014.pdf |archive-date=September 8, 2014 |url-status=dead }}</ref>

=== MP54AC ===
[[File:Malton ON GOT-668 MPI-MP54AC 2022-02-01 (2).jpg|thumb|An MPI MP54AC locomotive in the new [[GO Transit]] livery. [[GO Transit]] is currently the only operator of this model.]]
The MP54AC (also known as MP40PHTC-T4AC)<ref>{{cite web | url=https://www.railjournal.com/index.php/locomotives/motivepower-tier-4-diesel-delivered-to-go-transit.html | title=MotivePower Tier 4 diesel delivered to Go Transit | publisher=International Railway Journal | date=16 March 2018 | access-date=16 March 2018}}</ref> is the latest locomotive in the MPXpress family and the only model available for sale in the US. It is designed to both meet the EPA's stringent Tier 4 emissions standard and offer higher performance than the MP40PH-3C. The MP54AC is a [[genset locomotive]], using a pair of [[Cummins]] QSK60 60-liter, 16-cylinder engines rated at 2,700&nbsp;hp each (5,400&nbsp;hp total) and during periods of low power demand, the locomotive can operate on just one engine to reduce noise pollution and boost fuel efficiency. The 5,400&nbsp;total horsepower qualifies the MP54AC as the most powerful diesel-electric passenger locomotive in North America, both currently and historically.

Currently, the MP54AC can be built as new or by having existing MPXpress locomotives rebuilt to the standard.<ref>{{Cite web|url=https://www.wabtec.com/products/5103/mp54-ac-commuter-locomotive|title=MP54 AC Commuter Locomotive {{!}} Wabtec Corporation|website=www.wabtec.com|access-date=2016-11-28}}</ref>

GO Transit was the launch customer for the MP54AC. The first prototype unit was built by converting a MP40PH-3C owned by GO Transit (unit 647). MotivePower removed the EMD prime mover and HEP motor and replaced them with the twin Cummins engines. Heavy modifications were made to the body to accommodate extra air intake and exhaust stacks.<ref>{{cite web | url=https://www.wabtec.com/products/5103/mp54-ac-commuter-locomotive |title=MP54 AC COMMUTER LOCOMOTIVE |publisher=Wabtec Corporation |access-date=2015-12-16 }}</ref><ref>{{cite web|url=https://www.wabtec.com/uploads/MP54_QuickSpec_B.pdf|archive-url=https://web.archive.org/web/20151217161709/https://www.wabtec.com/uploads/MP54_QuickSpec_B.pdf|title=MP54AC|archive-date=December 17, 2015|publisher=Wabtec}}</ref> Unit 647 was delivered to GO Transit late 2015 and was seen under testing on December 12, 2015.<ref>{{cite web | url=http://www.railwayage.com/index.php/mechanical/locomotives/first-mp54ac-testing-on-go-transit.html?channel=35 |title=First MP54AC testing on GO Transit |date=14 December 2015 |publisher=Railway Age |access-date=2015-12-16 }}</ref>

Initially GO Transit had planned to convert a total of ten MP40PH-3Cs to the new MP54AC standard; it later ordered 16 additional newly built MP54AC locomotives instead.<ref>{{cite web | url=https://www.railwayage.com/passenger/commuterregional/prototype-mp54ac-delivered-to-metrolinx-go-transit/?RAchannel=home | title=Prototype MP54AC delivered to Metrolinx, GO Transit | publisher=Railway Age | date=2 March 2016 | access-date=16 March 2018}}</ref><ref>{{Cite web|url=https://transittoronto.ca/regional/2512.shtml|title=GO's MPI Series (MP40PH-3C and MP54AC) Locomotives (2007- ) – Transit Toronto – Content}}</ref>

The MP54AC competes with other Tier 4 compliant locomotives, such as the [[Siemens Charger]] series and the [[EMD F125]]. Both the MP54AC and F125 have struggled to find customers, unlike the Charger series, which has sold more than 450 units including large orders from [[Amtrak]] and [[Via Rail]].<ref>{{cite press release |url=https://media.amtrak.com/2018/12/amtrak-to-improve-national-network-with-new-locomotives/ |title=Amtrak to Improve National Network with New Locomotives |date=December 21, 2018 |publisher=Amtrak |access-date=October 19, 2020 |archive-date=January 26, 2021 |archive-url=https://web.archive.org/web/20210126125526/https://media.amtrak.com/2018/12/amtrak-to-improve-national-network-with-new-locomotives/ |url-status=dead }}</ref><ref>{{cite press release |url=https://www.siemens.com/ca/en/home/company/press/via.html |title=Siemens Canada secures major order with VIA Rail Canada for new fleet of passenger trains |publisher=Siemens Mobility |date=December 12, 2018}}</ref>

== Operators ==
{| class="wikitable"
!Railroad
!Model
!Qty.
!Notes
|-
|[[Caltrain]]
|MP36PH-3C
|6
|
|-
|[[FrontRunner]]
|MP36PH-3C
|18
|One unit sold to [[Northstar Line]]; two units sold to [[MBTA Commuter Rail|MBTA]]
|-
| rowspan="2" |[[GO Transit]]
|MP40PH-3C
|67
|One converted to an MP54AC
|-
|MP54AC|| 16
|One converted from MP40PH-3C
|-
|[[MARC Train|MARC]]
|MP36PH-3C
|26
|
|-
|[[Metrolink (California)|Metrolink]]
|MP36PH-3C
|15
|
|-
|[[MBTA Commuter Rail]]
|MP36PH-3C
|2
|Purchased from [[FrontRunner]]
|-
|[[Metra]]
|MP36PH-3S
|27
|Later converted to MP36PH-3C standard
|-
|[[New Mexico Rail Runner Express]]
|MP36PH-3C
|9
|
|-
|[[Northstar Line]]
|MP36PH-3C
|6
|Unit 512 purchased from [[FrontRunner]]
|-
|[[Sounder Commuter Rail|Sounder]]
|MP40PH-3C
|3
|Later rebuilt with lower-emission (Tier 3) engine.
|-
|[[SunRail]]
|MP32PH-Q
|11
|
|-
|[[Virginia Railway Express]]
|MP36PH-3C
|20
|
|-
|[[West Coast Express]]
|MP36PH-3C
|1
|
|-
!colspan=2 style="text-align:right"|Total
!227
!
|}

== Internal layout ==
{{expand section|date=March 2018}}
[[File:New Mexico RailRunner mp 36 cutaway png.png|left|thumb|700px|[[Cutaway drawing]] of New Mexico's RailRunner MPI MP36PH-3C. This layout varies for other locomotives.]]
{{clear}}

== References ==
{{reflist}}

== External links ==
{{Commons category|MPI MPXpress locomotives}}
* [https://www.wabteccorp.com/ Wabtec Corporation]

{{MPI Locomotives}}
{{Green Locos}}
{{EMD misc}}

[[Category:MPI locomotives]]
[[Category:B-B locomotives]]
[[Category:Passenger locomotives]]
[[Category:Diesel–electric locomotives of the United States]]
[[Category:EPA Tier 2-compliant locomotives of the United States]]
[[Category:Standard-gauge locomotives of the United States]]
[[Category:Standard-gauge locomotives of Canada]]
[[Category:Diesel–electric locomotives of Canada]]
[[Category:American Passenger Locomotives]]