Southern Pacific GE AC4400 228 at Carson, California, July 30, 1995. Photographer: Fred Quaas.

(Craig Garver, Public domain,


GE logo.


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 like the Dash 9-44CW, but features AC traction motors instead of DC, with a separate inverter per motor. In appearance, the AC4400CW is somewhat similar to GE's more powerful locomotive, the AC6000CW.

2,834 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.


CSX AC4400CW No. 209 in Newport News, Virginia, next to a former C&O coaling tower.

(William Grimes at English Wikipedia, Public domain, via Wikimedia Commons)


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, Cartier Railway, CSX for their units 200-599, Ferromex, Ferrosur, and KCS.

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.



In 2017, the Canadian Pacific Railway 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 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 AC4400CW-CTE. 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 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 completed from 2024-2028. The rebuilds are numbered in the 7000, 7200, and 7500 series and CSX is referring to them as CM44ACs.


UP AC44CW No. 6655 sits with a Union Pacific Railroad GE Evolution Series ES44AC No. 7494.

(Terling76, CC BY-SA 4.0 <>, via Wikimedia Commons)



Some AC4400CW owners and operators past and present include:

Owners Qty Numbers Year Delivered Notes
BNSF 121 5600-5717, 5838-5840 1999-2004 40 units leased to Metrolink from 2015 to 2016.
Canadian Pacific Kansas City 563 4500-4574, 4575-4596, 4597-4608, 4609-4624 (formerly 2000-2039), 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 AC44CWMs. renumbered 8100-8280 and CPKC 4500-4574 are ex-TFM/KCSM 2600-2674.
Cartier Railway 17 11-12, 13-17 and 18-29 2001-2007
Cerrejón 5 10010-10014 unknown
Chicago and North Western Transportation Company 35 8801-8835 1994 All to Union Pacific which became #6703 - #6737 by UP.
CIT Group 60 1001-1025, 1026-1059 2001-2004 1002 and 1006 sold to CMQ in 2017, and later returned in 2020s. 36 units sold to NS in 2023.
CSX Transportation 615 1-173, 201-599, 5101-5122 1994-2002 Units to be rebuilt to CM44AC/CM44AHs and renumbered to 7000-7299 and 7500 seriesCSXT 23 wrecked in 1996 and scrapped, CSXT 130 wrecked in 2018 and scrapped
Ferromex 75 4500-4549 and 4550-4574 1998-2000
Ferrominera del Orinoco 2 1058-1059 2004
Ferrosur 38 4400-4414, 4415-4429, 4430-4437 2000-2004
General Electric Corporation Leasing 11 2000, later renumbered 4400, 4000-4009 1993-1997
Norfolk Southern 36 3964-3999 2001-2004 (Acquired 2023) Ex-CEFX
Quebec, North Shore and Labrador 12 415-421 and 422-426 2005-2006
Southern Pacific 279 100-378 1995 All to Union Pacific 6148-6420. Unit 145 destroyed in wreck in 1996.
Union Pacific 1,338 5554-6887 and 7080-7297 1994-2004 Most units rebuilt to C44ACMs.
Totals 3,223

CP AC4400CW No. 9560 and CP SD40-2 No. 6029 head west towards the NS Elkhart Yard, 2009.

(Railfan Jack at English Wikipedia, CC BY-SA 3.0 <>, via Wikimedia Commons)


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.


Kansas City Southern AC4400CW No. 4575 with self-steering trucks in October 2014.

(Augy8400, CC BY-SA 4.0 <>, via Wikimedia Commons)



Type and origin
Power type: Diesel-electric
Builder: GE Transportation Systems
Model: AC4400CW
Build date: 1993 – 2004
Total produced: 2,834
​• AAR C-C
• UIC Co'Co'
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter: 42 in (1,067 mm)
Wheelbase: 13 ft 2 in (4.01 m)
Length: 73 ft 2 in (22.30 m)
Height: 15 ft 6 in (4.72 m)
Locomotive weight: 426,000 lb (193,000 kg)
Fuel capacity: 5,000 US gal (19,000 L; 4,200 imp gal)
Traction motors: 6
Performance figures
Power output: 4,400 hp (3,300 kW)
Tractive effort: 180,000 lbf (800 kN) Starting
Tractive effort: 145,000 lbf (640 kN) at 13.7 mph (22.0 km/h)
Operators: Various, see table above
Locale: North America