Editing EMD SD90MAC (section)

{{Short description|Model of American diesel-electric locomotive}}
{{Use dmy dates|date=November 2019}}
{{Original research|date=August 2021}}
{{Infobox locomotive
|  name=EMD SD90MAC and SD9043MAC
|  powertype=[[Diesel-electric]]
|  gauge={{track gauge|ussg}}
|  image=Union Pacific Railroad EMD SD90MAC-H.jpg<!--EMD_SD90MAC_UP_8512.jpg-->
|  caption=[[Union Pacific Railroad|UP]] 8540, an SD90MAC Phase II
|  builddate=1995–1999
|  totalproduction=657
|  buildmodel=SD90MAC
|  builder=[[Electro-Motive Diesel]] (EMD)
|  poweroutput={{Plainlist|
* SD9043MAC: {{convert|4300|hp|abbr=on|lk=in|sigfig=3}}
* SD90MAC: {{convert|6000|hp|abbr=on|lk=in|sigfig=3}}
}}
|  aarwheels=C-C
|  uicclass=Co’Co’
|  length={{convert|80|ft|2|in|abbr=on}}
|  locoweight={{convert|415000|lb|abbr=on}} (SD9043MAC) and {{convert|425000|lb|abbr=on}} (SD90MAC-H & SD90MAC-H2)
|  fuelcap={{convert|5000|usgal|abbr=on}}
|  sandcap={{convert|40|cuft|abbr=on}}
|  enginetype=[[V16 engine|V16]] [[Diesel engine|diesel]]
|  maxspeed={{convert|70|mph|km/h|0|abbr=on}} 
|  cylindercount=16
|  rpmrange=225-1,000 [[Revolutions per minute|rpm]]
|  wheeldiameter={{convert|45|in|mm|abbr=on}}
|  cylindersize={{convert|10.45|x|11.80|in|abbr=on}}
|  tractionmotors=6 [[Siemens]] 1TB2830 AC motors
|  tractiveeffort=Small engine (SD9043MAC): {{convert|185000|lbf|kN|abbr=on}} starting, {{convert|147000|lbf|kN|abbr=on}}   continuous<br />Large engine (SD90MAC-H and SD90MAC-H2): {{convert|200000|lbf|kN|abbr=on}} starting, {{convert|165000|lbf|kN|abbr=on}}  continuous
|  primemover=[[Electro-Motive Diesel|EMD]] [[EMD 710|16-710 G3C-T1]] and [[EMD 265|16-265H]]}}

The '''EMD SD90MAC''' is a model of {{convert|6,000|hp|abbr=on|lk=in|sigfig=3}}<ref>{{cite web |url=http://www.gmemd.com/en/locomotive/na_freight/sd90mac/index.htm |title=Gm Emd: Sd90Mac |website=www.gmemd.com |access-date=12 January 2022 |archive-url=https://web.archive.org/web/20011210220002/http://www.gmemd.com/en/locomotive/na_freight/sd90mac/index.htm |archive-date=10 December 2001 |url-status=dead}}</ref> [[AAR wheel arrangement#C-C|C-C]] [[Diesel-electric transmission|diesel-electric]] locomotive produced by [[Electro-Motive Diesel|General Motors Electro-Motive Division]] (EMD). It is, with the [[EMD SD80MAC|SD80MAC]], one of the largest single-engined locomotives produced by EMD and among the most powerful diesel-electric locomotives, surpassed only by the dual-engined [[EMD DDA40X|DDA40X]].

The '''SD9043MAC''' is the {{convert|4,300|hp|abbr=on|lk=in|sigfig=3}} variant, using a 16-cylinder [[EMD 710|710G engine]] instead of the [[EMD 265|H-engine]], which was originally intended as a temporary alternative while EMD tried to solve the [[EMD 265|H-engine's]] issues. However, the accompanying upgrade program was never utilized by its customers.

The SD90MAC's features include [[radial steering truck]]s with [[Alternating Current|AC]] [[traction motor]]s and an isolated [[cab (locomotive)|safety cab]] which is mounted on shock absorbers to lessen vibrations in the cab.  The SD90MAC, like the SD80MAC, [[EMD SD70ACe|SD70ACe]], and [[EMD SD70M-2|SD70M-2]], has a wide radiator section, nearly the entire width of the locomotive, which along with their size makes them easy to spot.

As of 2019, some SD90MACs are still in service on the Union Pacific. Norfolk Southern had rostered 110 SD90MAC locomotives purchased or traded from Union Pacific or  the CIT Group respectively, that have now all been rebuilt as [[EMD SD70ACU]] locomotives. Canadian Pacific has also opted to convert their small fleet of long-stored SD90MACs into SD70ACUs as well.