# GE AC4400CW

The GE AC4400CW, sometimes referred as "AC44CW", is a 4,400 horsepower (3,300 kW) diesel-electric locomotive that was built by GE Transportation Systems between 1993 and 2004. It is similar to the Dash 9-44CW, but uses AC traction motors instead of DC, with a separate inverter per motor.
3,018 units were built for North American railroads over an 11-year production. In 2005, all Class I freight railroads except Norfolk Southern and Canadian National owned at least one AC4400CW. Norfolk Southern ordered the very similar C40-9Ws, although NS would later acquire 36 former CEFX AC4400CWs in August 2023. As a result of more stringent emissions requirements that came into effect on January of that year, GE no longer offers the AC4400CW, replacing it with the ES44AC.

## Design variations

The AC4400CW was the first GE locomotive to offer an optional self-steering truck design, intended to increase adhesion and reduce wear on the railhead. This option was specified by Canadian Pacific Railway, Cartier Railway, CSX for their units 201-599, Ferromex, Ferrosur, and Kansas City Southern Railway. The other railroads still used the hi-ad truck design
CSX ordered many of its AC4400CW locomotives with 20,000 lb (9,100 kg) extra weight to increase tractive effort. These same units were also modified in 2006-2007 with a "high tractive effort" software upgrade and redesignated CW44AH.

## Rebuilds

In 2017, Canadian Pacific Kansas City (then known as the Canadian Pacific Railway and simply Canadian Pacific) requested that General Electric modernize 30 of its 9500 and 9600-series AC4400CW units. The original units had the original front cab completely removed and upgraded to current GE standards with upgraded electrical systems including PTC and FTO systems. Other improvements GE has made include up to 10 percent fuel efficiency gains, 40 percent increase in reliability and 50 percent increase in haulage ability. The units were subsequently placed into service with the designation AC4400CWM (for Modernized). The first batch of rebuilds (8100-8129) also had their original Steerable trucks replaced with GEs High Adhesion trucks, where later batches each individual engine kept the trucks they already had.
The following year Canadian Pacific Kansas City asked GE to similarly rebuild several more batches for a total of 110 locomotives. The second order (8130-8144) retains their steerable trucks. The third batch (8000-8064) will feature an Evolution Series sized fuel tank and radial trucks. In 2019 a fourth batch of rebuilds happened, 8145-8160 & 8064-8080 from the 95/9600-series. In 2021 both the 8500 series is slated to be rebuilt at 8201-8280 and the 8100-series be completed.
The Union Pacific Railroad (UP) ordered many of their AC4400CWs with Controlled Tractive Effort software, giving them the designation of C44ACCTE. This software package is now standard on a portion of their ES44ACs as well. CTE limits tractive effort to mimic TE level of Dash series locomotives. In late 2023, they will all be rebuilt into C44ACMs.
In 2018, UP placed a small order for 20 rebuilds from GE of their AC4460CW fleet and later announced that they would be upgrading 1,000 of their AC4460CWs and AC44s into the new C44ACM class over the next 15 years. Unlike CP, the original 20 rebuilds did not receive a new crew cab.
CSX also placed orders to rebuild their large AC4400CW fleet. An initial batch of 10 AC4400CWs were rebuilt at Wabtec's Erie, Pennsylvania facility, with 40 more to follow. CSX continued the program and had received a total of 260 rebuilt locomotives by 2024. A final order has been placed to rebuild the remaining 200 plus locomotives and will be compled from 2024-2028. The rebuilds are numbered in the 7000-7600 series and CSX is referring to them as CM44ACs and CM44AHs.
NS recently acquired 36 of these locomotives from CEFX in June 2023. They are currently being patched for starting service on the roster. These units will be rebuilt to AC44C6M locomotives (similar to the ones from the Dash 9 locomotives) at the Wabtec locomotive plant in Fort Worth, TX. The first unit, NS 3980, was the first unit to be rebuilt into an AC44C6M and it's undergoing testing at the Wabtec facility. NS planned to rebuild 25 of the 36 of these units, but they failed to be delivered to NS. They were sold to Wabtec then to FXE.

## Operators

AC4400CW owners and operators past and present include:
| Owners | Qty | Numbers | Year delivered | Notes |
| Union Pacific | 1,169 | 5554-5694, 5700-6081, 6430-6702, 6738-6887, 6995-6999, and 7080-7297 | 1994-2004 | Most units rebuilt to C44ACMs. Units 6700-6702 were renumbered from 9997-9999. Minimal units were wrecked and retired. 5554-5694 and 5700-6081 are classified as C44ACCTE by UP. |
| CSX Transportation | 594 | 3-174, 201-599, 5101-5122 | 1994-2002 | Units to be rebuilt to CM44AC/CM44AHs and renumbered to 7000-7600 series. Some units were wrecked and retired before the rebuild. 1-14 were former 9100-9113. Unit 7005 (formerly 14) was wrecked in March 2023 and retired. 1 and 2 were renumbered to 173 (2nd) and 174 respectively. |
| Canadian Pacific Kansas City | 563 | 4500-4624, 8500-8580, 8600-8655, 9500-9683, 9700-9740, 9750-9784 and 9800-9840. | 1995-2004 | 9777, 9782, 9758, and 9751 used during filming of Unstoppable. Most units rebuilt to AC4400CWMs. Renumbered to the 8000-8080, 8100-8178, and 8200-8210 series, and CPKC 4500-4574 are ex-TFM/KCSM 2600-2674. 4575-4624 were renumbered from 2000-2049. 9813 was wrecked and retired. |
| Southern Pacific | 279 | 100-378 | 1995 | All to Union Pacific 6145-6425. Unit 145 and 224 destroyed in wreck in 1996. |
| BNSF | 121 | 5600-5717, 5838-5840 | 1999-2004 | 40 units leased to Metrolink from 2015 to 2016. 5701 was wrecked and scrapped. 5838-5840 are warranty protection units. |
| Ferromex | 75 | 4500-4574 | 1998-2000 | 4508 was wrecked and retired. |
| CIT Group | 59 | 1001-1059 | 2001-2004 | 1002 and 1006 sold to CMQ in 2017, and later returned in 2020s. 36 units sold to NS in 2023. |
| Ferrosur | 38 | 4400-4437 | 2000-2004 | |
| Chicago and North Western Transportation Company | 35 | 8801-8835 | 1994 | All to Union Pacific which became #6703 - #6737 by UP. 6707 was wrecked and retired. |
| Cartier Railway | 19 | 11-29 | 2001-2007 | |
| Quebec, North Shore and Labrador | 12 | 415-426 | 2005-2006 | |
| Cerrejón | 5 | 10010-10014 | unknown | |
| General Electric Corporation Leasing | 11 | 2000, later renumbered 4400, 4000-4009 | 1993-1997 | 4000-4009 have been sold to UP as 7000-7009. 7007 has been rebuilt to C44ACM. |
| Ferrominera del Orinoco | 2 | 1058-1059 | 2004 | |
| Norfolk Southern | 36 | 3964-3999 | 2001-2004 (Acquired 2023) | Ex-CEFX. The units will be rebuilt into AC44C6M. The units failed to be delivered, and 25 were sold to Wabtec then FXE |
| Totals | 3,018 | | | |

## In popular culture

The plot of the movie Unstoppable required Denzel Washington and Chris Pine to climb aboard the lead locomotive of a runaway freight train. To film the movie, four Canadian Pacific AC4400CW locomotives (Nos. 9777, 9758, 9782, and 9751), were repainted as two fictional "Allegheny and West Virginia Railroad" locomotives (Nos. 777 (nicknamed "Triple 7") and 767). 9777 and 9782 were painted as 777, while 9758 and 9751 were painted as 767.