The EMD (Electro Motive Division) GP9 is a type of four-axle, 16-cylinder, 1,750hp type of diesel locomotive built by the Electro Motive Division of General Motors (GM) from 1954 to around 1963.

An SP (Southern Pacific) GP9. The road was originally one of the largest owners for the type of road-switcher, and utilized them for almost every train.

It is the successor to the GP7; being an improvement over the previous model, but is also considered to be the non-cab unit (non-streamlined or carbodied) or road-switcher version of the F9.

Many were built (being a total of 4,115 with at least 165 B-units), and many still currently operate on various shortlines and/or regionals, while a plethora are preserved in museums either on static display, or are operational. Though many have since been scrapped, rebuilt, and/or retired.

As of 2014, 4 major Class 1 railroads or railways throughout North America roster GP9's. Canadian railways such as Canadian Pacific (CP), CN Rail (Canadian National), and Mexican railways like Ferromex (FXE) and its subsidiaries currently operate a number of both true (non-rebuilt/upgraded) and rebuilt GP9's (which include such rebuilds as the GP9R, GP9u, GP22ECO, GP28M, GP9-4, and GP9M or GP9RM). BNSF is currently the only US Class 1 railroad to roster GP9 units. One unit (BNSF #1685) is currently assigned to their Canadian Manitoba operations, while another unit (BNSF/GN #1703) was rebuilt into a remote-controlled B-Unit with a covered control stand on the engineer's side of the front hood, and has been in operation at the railroad's Lincoln, NE facility since it was first rebuilt from a GN GP9 cab unit ("A-Unit") in the 1970s. 

Numerous South American railways such as América Latina Logística (ALL) along with various other Latin American railways throughout the region, operate fleets of units as well for primary, secondary, local, and yard services.

BNSF was recently the last US Class 1 railroad or carrier to operate a small fleet of GP9 or GP9u units for yard service (including several GP7u's). They have since been retired, though many of their ex-BN GP28M units rebuilt from GP7/GP9 ancestry still remain in active service. 


Although the initial success of its predecessor meant a brighter future for EMD, it also meant that there was


still room for more potential and improvement. In October 1954, the first ever GP9 unit was produced, and signified the next generation of progress and success for the company. In otherwords, the GP9 served as a somewhat drastic improvement (in comparison to reports from various experienced engineers and crewmembers) to the GP7 in terms of having better tractive effort, improved weight distribution, and a much more reliable dynamic braking system (which became state-of-the-art at the time) which was even better than what was previously offered with later-production GP7 units.

A transitional model, the GP9 served as a milestone or turning point between the traditional roots-blown (non-turbocharged) aspirated diesels, and the more modern turbocharged models which are currently in primary service today. Beginning with models like the GP20 and SD24, modern motive power has since been forever changed upon the success of the two models, for roots-blown models like the GP9 and succeeding models like the GP18 to the GP38-2 have since been re-regulated for secondary service as yard switchers, local job units, or as spares rather than primary road switchers or as mainline freight locomotives.

Railroads such as the Union Pacific (UP), Southern Pacific (SP), Chesapeake And Ohio (C&O), the Milwaukee Road (MILW), Illinois Central (IC), New York Central (NYC), Pennsylvania Railroad (PRR), Northern Pacific (NP), and the Chicago And Northwestern (CNW) were among the many companies whom rostered units to utilize as road-switchers: diesel locomotives that were originally designated as yard switchers used for sorting freight cars to and from yards and mainlines, but were eventually utilized as multi-purpose diesels for any service (as with future GP series models like the GP40).

Because of the model's increasing popularity, EMD eventually offered a cabless "booster" variant (known as a "GP9B") 

Boston & Maine GP9 77 2

Pan Am (formally Guilford Rail/Springfield Terminal nee Boston And Maine) #77 (dressed in Boston And Maine livery) is an example of one of the several heritage units painted in a commemorate livery dedicating the numerous railroads which once operated within the corporation's system. Ironically, the railroad never painted their GP9 units in such scheme.

which helped railroads reduce the amount of time taken to rearrange a consist on a train. Only about 165 were built, and only a handful of original production units are known to still exist, though most have been rebuilt or converted to "A units". "B units" were mostly utilized by the PRR (later Penn Central) as well as the UP.

After the GP9's initial demonstration and introduction, the model became ordered by many railroads almost instantly; despite said railroads already owning preceeding GP7 units.

The introduction of the 1,800hp GP18 eventually replaced the GP9 in EMD's catalogue, which spelled the end of the model's production.

Spotting FeaturesEdit

Although vaguely similar in appearance to the preceding GP7, the GP9 has numerous external and internal differences. Among these differences are:

  • Shorter wheelbase (on most GP9 units, including several later-production GP7's).
  • Thinner frame
  • Shorter fuel tank
  • Different airtank/air reservoir placements
  • Taller/larger radiator fans
  • Dual control stands (for most GP9's; some GP7's owned by the Western Pacific utilized them as well).



An SP GP9 leading a San Francisco Bay Area commuter train.

Although only 145 GP9B units were built, several "cabbed" ("cab unit", or "A-unit") original GP9 units were eventually rebuilt later-on into their careers as a result of being wrecked, converted, or kitbashed from several various scrapped diesels and classified as such (or in some cases, "GP9RB" as with the GTW's fleet of rebuilt GP9/GP7 units).

Many rebuilt GP7 units are often classified as being a "GP9" or "GP9M" ("M" meaning, "modified"), considering that they are often regarded as being improved from their predecessor. Furthermore, most "GP9M" units are also rebuilt from scrapped, wrecked, or damaged F Units (considering that they use the exact same frame type or style as well as having the same version of EMD 567 series engine; being the 567C, 567B, or 567D).

In the 2014 remake of Godzilla, a GP9 is featured hauling a military train loaded with a nuclear warhead missle in the film. Oddly, the unit emits a generic EMD turbocharged sound effect; despite being roots-blown (non-turbocharged).

4 GP9/GP7 units from mixed GN and ATSF heritage were rebuilt into remote-controlled, battery-operated yard slugs for BNSF by RailPower (BNSF #1210-1213) in 2005. Despite being considered cabless, the remnants of their cabs were repurposed as control boxes for housing the on-board controller equipment. Although revolutionary, the units were problematic during their short-lived careers, and were scrapped by 2009. 


SourcesEdit (BNSF GG20B)

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