New Jersey Transit PL42AC No. 4029 at Convent Station.

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


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The Alstom PL42AC is a class of four axle B-B diesel-electric locomotive designed by Alstom in association with GM-EMD. 33 were built between 2003 and 2006 for NJ Transit Rail Operations.



The PL42AC is a diesel-electric 4-axle locomotive built by Alstom with 16-710G3B prime mover for New Jersey Transit. The first two locomotives were manufactured at the Meinfesa plant in Valencia, Spain in 2003. The 31 following units were assembled at the Alstom Transport plant in Hornell, New York in 2004, and were produced through early 2006. The power rating of the PL42AC locomotives is 4,200 hp (3.1 MW) total for tractive effort and head-end power. The locomotive has a design similar to the GE Genesis, mainly due to the fact that both PL42AC and Genesis series locomotives were designed by industrial designer Cesar Vergara.

This locomotive uses IGBT technology with precise traction computers for tractive effort. The PL42AC has 800 kilowatts head-end power and WABCO's EPIC II braking system, along with an E-7 wheel slide device, made by Wabtec, preventing flats spots on the wheels through software and hardware.

It has an Intelligent Display Unit (IDU) based on Bombardier Transportation technology from which an engineer or technician can view data or download events and faults from the previous weeks or months. The technician can do a host of tests from the IDU to determine if a specific system is operating correctly.

The PL42AC uses computer hardware and software to control functions and to protect the engine. For example, if the on-board computer detects too little oil in the system, it will shut down the engine to avoid damage.



In July 2020, NJ Transit announced that older locomotives in the PL42AC fleet will be replaced by additional ALP-45A dual mode locomotives, due to the PL42AC's unreliability and inability to be upgraded to meet new Environmental Protection Agency standards. Of the 33 units, 23 are slated for replacement, while the remaining 10 will receive a light overhaul for continued service.



Type and origin
Power type: Diesel-electric
Builder: Alstom, EMD
Model: PL42AC
Build date: 2003–2006
Total produced: 33
​• AAR B-B
• UIC Bo′Bo′
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter: 42 in (1,067 mm)
Length: 69 ft 10 in (21.29 m)
Width: 10 ft 8 in (3.25 m)
Height: 15 ft 5 in (4.70 m)
Locomotive weight: 287,000 lb (130,000 kg)
Fuel capacity: 2,250 US gal (1,870 imp gal; 8,500 L)
Prime mover: EMD 16-710G3B-T1
Engine type: V16, two-stroke diesel
Alternator: TA-17
Head end power: 800 kW (1,100 hp)
Cylinders: 16
Performance figures
Maximum speed: 100 mph (160 km/h)
Power output at alternator: 4,200 hp (3.1 MW)
Power output at rail: 3,620 hp (2.70 MW) MAX with HEP on
Tractive effort starting: 69,975 lbf (311.26 kN)
Tractive effort continuous: 27,000 lbf (120 kN)
Operators: NJ Transit
Numbers: 4000–4032