Pennsylvania Railroad (PRR) Electric Roster: All Classes

Published: September 23, 2026

The Pennsylvania Railroad’s electric locomotives were two plants, not one. From 1910 the Hudson and East River tunnels into Pennsylvania Station ran on 650-volt DC third rail, and the motors for that job were side-rod DD1s. From 1915 the railroad strung 11,000-volt, 25-cycle catenary, first to Paoli, then down to Washington on February 10, 1935, and west to Harrisburg for passenger trains on January 15, 1938. Everything from the P5 to the E44 was built for that wire. The class letters are the same letters the railroad used on steam. A B is an 0-6-0. A P is a Pacific. A GG is two 4-6-0s back to back. Multiple-unit cars are not in this list. The GG1’s unit roster is the GG1 page. The yard switchers, unit by unit, are the B1 page.

1960s postcard of a Pennsylvania Railroad GG1 electric locomotive

A 1960s postcard GG1. The class handled passenger trains and, when required, freight. Author’s collection.

On this page: At a glance · Third rail · The first AC motors · Switchers · Looking for a passenger motor · Freight, rectifiers, and the E44 · Class roster · Sources

At a glance

Item	Detail
Railroad	Pennsylvania Railroad. Electric operations through January 31, 1968. Penn Central from February 1
Third rail	650 volts DC. New York terminal, 1910. Classes AA1, DD1, and the DC L5s
Catenary	11,000 volts, 25 cycles. Paoli 1915. New York–Washington completed February 10, 1935. Harrisburg passenger trains January 15, 1938
Production passenger motor	GG1. 139 locomotives, 4800–4938, 1934–1943
Production freight motor	E44. 66 locomotives, 4400–4465, General Electric, 1960–1963
Switchers	28 Pennsylvania B1s. The Long Island’s 14 B3s are the same carbody and a different roster
How a DD1 is counted	Two carbodies, drawbar-coupled, are one locomotive. The class table uses that count
Diesels	Pennsylvania diesel roster

Class lines follow Classic Trains’ 2021 survey except where the B1 page or the GG1 page is the closer source. Information compiled September 23, 2026.

Third rail into Penn Station

Steam could not run the Hudson tubes. While the station was being planned, Altoona built two experimental third-rail units, class AA1, numbers 10001 and 10002, in 1905. Westinghouse supplied the electrical equipment. They were B+B machines, a pair of four-wheel trucks, and they were scrapped after they had done their job as test beds. The locomotive that came out of that work was the DD1.

A DD1 is two 4-4-0 carbodies coupled back to back, each with a jackshaft and side rods, and the railroad counted the pair as one locomotive. Juniata and Westinghouse built 33 of them in 1909–1911. The carbodies are numbered in the 3932–3999 series, which also includes two earlier odd-DD pairs, and the series is not solid: 3950 and 3951 are not a DD1. Horsepower for a pair was 3,160, on 650-volt DC third rail. They took passenger trains from Manhattan Transfer, through the station, and out to Sunnyside Yard in Queens. When the L5s arrived in 1924, many DD1s moved to the Long Island for freight. One pair lasted long enough to be saved: 3936 and 3937, at the Railroad Museum of Pennsylvania.

The L5 was supposed to be the next step, a single-unit side-rod motor with a 1-B-B-1 arrangement, usable as a passenger engine or a mountain freight engine and, in theory, on either kind of current. It was not. One AC prototype, class L5paw, number 3930, was built in 1924. Twenty-three DC third-rail locomotives, 3922–3929 and 7801–7815, followed through 1928, with Westinghouse and Brown Boveri electrical equipment. They were meant to help the DD1s between Sunnyside and Manhattan Transfer. They were worse at it than the engines they were sent to replace. The long rigid wheelbase and the weight distribution limited them, and they were gone from that job by the early 1930s, when AC catenary reached the terminal. All of them were scrapped.

Pennsylvania Railroad FF2 electric number 5, a 1-C plus C-1, at Thorndale Pennsylvania circa 1960

FF2 #5, a 1-C+C-1, at Thorndale, circa 1960. These were Great Northern Y-1s from the Cascade Tunnel electrification. The Great Northern shut that operation down in 1956, and the Pennsylvania bought most of the motors, classed them FF2, and scrapped them in the 1960s.

The first AC motors

Before the tunnels, Baldwin and Westinghouse had already tried single-phase AC. In 1907 they built one 2-B boxcab, number 10003, the "odd class D," and tested it under a short stretch of catenary on the Long Island. It made about 750 horsepower. It did not go into production. It did show that two such engines, set back to back, could be a road locomotive, which is the idea the DD1 later used on direct current.

The other early one-off was built for a railroad that was never wired. Class FF1 number 3931, "Big Liz," came out of Juniata in 1917: a 1-C+C-1 side-rod freight motor of about 4,000 horsepower, meant for a catenary main line over the Alleghenies. That electrification was never built. Big Liz spent her life as a helper between Philadelphia and Paoli, on the 1915 Paoli wire, and was scrapped in 1940.

Pennsylvania Railroad P5a electric 4769 at Enola Pennsylvania on August 22 1962

P5a #4769, a 2-C-2, at Enola, August 22, 1962. The P5a was the rebuilt form of the P5, with the cab moved out of the center of the box after the original arrangement proved dangerous in a collision. Bill Volkmer photo. American-Rails.com collection.

Switchers

Once coach yards sat under wire, a steam 0-6-0 was the wrong shifter. Juniata’s answer was a three-axle boxcab, class B, the same letter the railroad used for a steam six-wheel switcher. Twenty-eight of them were Pennsylvania engines. The first twenty-eight carbodies of 1926 were built as married pairs: BB1 numbers 3900 and 3901, AC from the start, and BB2 numbers 3910–3921, twelve DC third-rail locomotives in six pairs for Sunnyside and Penn Station. In 1933 the pairs were split, the DC engines were converted to 11,000-volt AC, and everything was reclassed B1. Fourteen more, 5684–5697, were built in 1934–35 as single units, Allis-Chalmers electrical equipment, for Philadelphia and for Harrisburg as the passenger wire moved west.

Three motors, 233 horsepower each, come to about 700 horsepower. Classic Trains prints 570 horsepower for the class, which is the continuous figure against that hourly rating. Crews called them rats. 5690 is the survivor, indoors at Strasburg. It was briefly Penn Central 4756. The Long Island’s fourteen Bay Ridge freight motors, class B3, are the same Altoona machine and a different roster. The unit list, construction numbers, and the 1966–67 renumbering are the B1 page.

Looking for a passenger motor

The wire east of Harrisburg needed a passenger locomotive, and the railroad spent a decade finding one. Eight class O1 experimentals, numbers 7850–7857, were built in 1930–31 on a 2-B-2 wheel arrangement, with Westinghouse, General Electric, and Brown Boveri electrical equipment split across subclasses O1, O1a, O1b, and O1c. They were light, 2,000 to 2,500 horsepower, and they were often doubled. They were not repeated.

The production try was the P5. Ninety-two locomotives, class P5 and P5a, were built from 1931 to 1935 by the railroad, Baldwin, and General Electric, on a 2-C-2 arrangement, at 3,750 horsepower. The two prototypes, 7898 and 7899, became 4700 and 4791. The other ninety are 4701–4790. The first sixty-four of the family were boxcabs, cab at each end. After a grade-crossing collision killed the crew in the nose of a boxcab, the rest were built with a center cab and a streamlined nose, classed P5a modified: 4743–4754 and 4775–4790, twenty-eight locomotives. No. 4770, a boxcab, was later rebuilt to the modified form. No. 4702 was rebuilt in 1937 to 5,000 horsepower and reclassed P5b. That was a rebuild, not a new order.

The P5 was a hard-riding passenger engine. The driving axles took a beating from the torque, and the railroad moved the class to freight, where the motors worked into the early 1960s. One of them is preserved. The search for a replacement produced two prototypes in 1934. Baldwin-Westinghouse built the R1, a rigid 2-D-2, originally numbered 4800. General Electric and the railroad built the GG1, a 2-C+C-2 with an articulated frame. The GG1 tracked better. It got the order. The R1 was renumbered 4899 in November 1934, when the GG1 prototype took 4800, and became 4999 in 1940. It stayed in passenger service for about twenty years and was scrapped in the 1950s.

The GG1 that won is 139 locomotives, 4800–4938, built from 1934 to 1943, continuous rating 4,620 horsepower. No. 4800 is Old Rivets, the riveted prototype. Builders, weights, gear ratios, the Amtrak numbers, and the last revenue trip are the class page, not this one. A single later experiment, class DD2 number 5800, tried in 1938 to get GG1-sized power out of a 2-B+B-2. It was geared for freight, it stayed unique, and it was scrapped in 1962.

The freight design that lost out to the reassigned P5s was the L6. Two prototypes, 7825 and 7826, later 5938 and 5939, and one Lima-built L6a, number 5940, were 1-D-1 boxcabs of 2,500 horsepower, built in 1931–34. The 5940 was the first of a thirty-unit Lima order that was cancelled. The three worked as switchers around New York into the 1960s and were scrapped.

Freight, rectifiers, and the E44

By the early 1950s the P5s were old and the railroad still had no new freight motor. It bought ten experimentals. General Electric delivered six class E2b locomotives, 4939–4944, a B-B carbody with AC traction motors, 2,500 horsepower. Four of them, 4939–4942, came in 1951–52. The last pair, 4943 and 4944, were GE demonstrators, bought in 1953. They were usually run as pairs. Baldwin-Westinghouse delivered four more in 1951, and these were the important ones: ignitron rectifiers turned the AC from the wire into DC for ordinary traction motors. E3b numbers 4995 and 4996 rode on a B-B-B arrangement. E3c numbers 4997 and 4998 were C-C. All ten experimentals were scrapped in 1964. Baldwin-Westinghouse was already out of the locomotive business. The rectifier idea was not.

While that test was going on, the Great Northern shut down the Cascade Tunnel electrification. In 1956 the Pennsylvania bought seven of GN’s Y-1 boxcabs, Alco-GE motors of 1927–30, and classed them FF2, numbers 1–7. They were 1-C+C-1 machines of about 3,300 horsepower, used as freight engines and helpers west of Philadelphia, and they were scrapped between 1960 and 1965. They are the only secondhand electrics on this roster.

The production freight locomotive was the E44. General Electric built 66 of them, 4400–4465, in 1960–1963, a C-C road-switcher body on the ignitron-rectifier pattern of the E3s, rated 4,400 horsepower. The locomotives at the end of the order were built with silicon-diode rectifiers, rated 5,000 horsepower, and classed E44a. The Penn Central roster treats 4458–4465 as that block. Classic Trains counts the as-built silicon units as the final six. Others were converted later, until the Penn Central bankruptcy stopped the program. The class is the E44 page. No. 4465 is preserved at Strasburg. The fleet was still intact when Conrail ended electric freight in 1980.

Pennsylvania GG1s 4925 and 4886 westbound at Paoli Pennsylvania with a mail and express train in February 1968

GG1s #4925 and #4886 westbound at Paoli, Pennsylvania, with a long mail and express train for Harrisburg, just after the Penn Central merger, February 1968. Don Sims photo.

Class roster

A DD1 row is one drawbar-coupled pair. Long Island B3 switchers are not in the table. GG1 road numbers and builders are not repeated unit by unit.

Class	Arrangement	Numbers	Qty	Built	Current	Notes
AA1	B+B	10001, 10002	2	1905	650 V DC third rail	Tunnel experiments. Both scrapped. 1,400 hp and 1,240 hp
Odd D	2-B	10003	1	1907	11 kV AC	Baldwin-Westinghouse. Tested on Long Island catenary. About 750 hp. Scrapped
DD1	2-B+B-2	3932–3999 series	33	1909–1911	650 V DC third rail	Each locomotive is a coupled pair. Includes two odd-DD pairs. 3,160 hp. 3936–3937 preserved. 3950–3951 are not a DD1
FF1	1-C+C-1	3931	1	1917	11 kV AC	Big Liz. About 4,000 hp. Paoli helper. Scrapped 1940
L5paw	1-B-B-1	3930	1	1924	11 kV AC	AC prototype. 3,040 hp. Scrapped
L5 (DC)	1-B-B-1	3922–3929, 7801–7815	23	1924–1928	650 V DC third rail	Westinghouse and Brown Boveri. Off the New York passenger job by the early 1930s. All scrapped
BB1 / B1	C	3900–3901	2	1926	11 kV AC	Built as one AC pair. Split and reclassed B1 in 1933
BB2 / B1	C	3910–3921	12	1926	DC, then AC	Six DC pairs. Split and converted to AC, 1933–35
B1	C	5684–5697	14	1934–1935	11 kV AC	Built as singles. About 700 hp hourly. 5690 preserved. See the B1 roster
O1 / O1a / O1b / O1c	2-B-2	7850–7857	8	1930–1931	11 kV AC	Passenger experimentals, 2,000–2,500 hp. Often doubled. All scrapped
P5 / P5a	2-C-2	4700–4791	92	1931–1935	11 kV AC	3,750 hp. Prototypes 7898–7899 became 4700 and 4791. Boxcabs, then 28 center-cab "modified." 4702 rebuilt as 5,000 hp P5b. Moved to freight. One preserved
L6 / L6a	1-D-1	5938–5939, 5940	3	1931–1934	11 kV AC	Built as 7825–7826 and Lima 5940. 2,500 hp. A 30-unit Lima order was cancelled. New York switchers into the 1960s
R1	2-D-2	4999	1	1934	11 kV AC	Built as 4800. Became 4899 in November 1934, then 4999 in 1940. Baldwin-Westinghouse. About 5,000 hp. Scrapped in the 1950s
GG1	2-C+C-2	4800–4938	139	1934–1943	11 kV AC	4,620 hp continuous. 4800 is Old Rivets. Unit roster is the GG1 page
DD2	2-B+B-2	5800	1	1938	11 kV AC	About 5,000 hp. Geared for freight. Scrapped 1962
E2b	B-B	4939–4944	6	1951–1953	11 kV AC	GE. AC traction motors. 2,500 hp. 4943–4944 were demonstrators. Scrapped 1964
E3b	B-B-B	4995–4996	2	1951	11 kV AC	Baldwin-Westinghouse. Ignitron rectifiers. 3,000 hp. Scrapped 1964
E3c	C-C	4997–4998	2	1951	11 kV AC	Same order as the E3b. Scrapped 1964
FF2	1-C+C-1	1–7	7	1927–1930	11 kV AC	Ex-Great Northern Y-1, bought 1956. About 3,300 hp. Scrapped 1960–1965
E44 / E44a	C-C	4400–4465	66	1960–1963	11 kV AC	GE. 4,400 hp. Silicon-diode E44a units at 5,000 hp; Penn Central classes 4458–4465 as E44a. 4465 preserved. See the E44 page

What those numbers became after February 1, 1968, is the electric section of the Penn Central diesel roster. The company that ran them until then is the Penn Central page.

Sources

Robert S. McGonigal, "Pennsylvania Railroad electric locomotives," Classic Trains, January 14, 2021. Class list, wheel arrangements, quantities, horsepower, and the P5 number split.
Eugene Connelly and William Edson, PRR numerical roster of steam and electric locomotives, as used on the B1 page. Twenty-eight Pennsylvania switchers. Long Island’s fourteen B3s stay off this table. 5690, briefly Penn Central 4756.
Michael Bezilla, Electric Traction on the Pennsylvania Railroad, 1895–1968. The tunnel plant and the 1928–38 catenary program. Paoli 1915, New York–Washington February 10, 1935, Harrisburg passenger service January 15, 1938, are the dates used on the company page.
Alvin F. Staufer and Bert Pennypacker, Pennsy Power (1962), for the B1 motors and the P5 / GG1 generation.
GG1 class page. 139 locomotives, 4800–4938, continuous 4,620 horsepower. R1 number swap, November 1934 and 1940. Conrail freight electrics ended in 1980.
E44 class page, and the Penn Central roster’s E44 / E44a split.