C O N T E N T S

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1. Diesel locomotive history . . . . . . . . . . . . . . . . . . . 6

2. How diesel locomotives work . . . . . . . . . . . . . . . 26

3. Details and options . . . . . . . . . . . . . . . . . . . . . . . 37

4. Locomotive types . . . . . . . . . . . . . . . . . . . . . . . . . 45

5. EMD diesels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

6. General Electric diesels . . . . . . . . . . . . . . . . . . . . 92

7. Alco diesels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

8. Baldwin and Lima diesels . . . . . . . . . . . . . . . . . 127

9. Fairbanks-Morse diesels . . . . . . . . . . . . . . . . . . 136

10. Rebuilds, slugs, and hydraulics . . . . . . . . . . . . 142

Rosters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

Appendix: List of railroad abbreviations . . . . . . . . 302

 Starting in the 1920s, manufacturers
realized that pairing an internal-combus-
tion engine with a generator and electric
motors on the axles had great promise for
locomotives. Starting with small switching
locomotives and progressing to ever-larger
road locomotives, diesels eventually over-
took steam locomotives. By the 1960s,
steam was history, and diesel progression
continued with the evolution of micropro-
cessor control and AC traction motors.
Today’s 4,400-horsepower locomotives are
powerful, fuel-efficient, reliable, technolog-
ical marvels, but they still trace their roots
to the pioneering locomotives of the 1930s
and ’40s.

Builders and models

By the 1940s, five major diesel locomotive
builders had emerged: Electro-Motive
(EMD), American Locomotive Co. (Alco),
Baldwin, Fairbanks-Morse, and Lima. By
the late 1950s this had dwindled to two—
EMD and Alco—but then General Elec-
tric joined in, shortly relegating Alco to Long Island Rail Road No. 401, a 100-ton boxcab built by Alco/GE/Ingersoll-Rand, is
third place before Alco finally left the often credited with being the first road diesel-electric in the U.S. Long Island Rail Road
business in 1969. The market has belonged
to EMD and GE since then. whether a locomotive is equipped with include as-delivered road numbers (sec-
Manufacturers offer a variety of models dynamic brakes or a steam generator. ondary owners are not included).
for different purposes, including switching, Locomotive model numbers or designa- Tables in each of these chapters provide
— I N T RO D U CTIO N — passenger, and freight service, with each tions sometimes make sense, (often follow- the total number built for each locomotive
often available in varying horsepower rat- ing the horsepower rating and number of type, timelines of the period each was built
ings. Most diesel locomotive models axles), but often they don’t—especially for (black lines), with an estimation of the
remain in production for several years, EMD, long the dominant locomotive years they remained in service (shaded gray
unlike automobiles, where a new model is builder. The chapters on manufacturers lines). Use these as general guides, as with
introduced each year. Locomotive builders include a description of each builder’s the thousands of locomotives built (and
generally introduce new models for signifi- nomenclature. later rebuilt) it’s impossible to verify the

W
Electro-Motive’s GP7, introduced in hether you are a railfan, modeler, history buff, or any cant changes, such as a boost in horse- exact dates that all samples of a certain
1949, wasn’t the first road power or change in engine (prime mover). What’s included model are out of service.
switcher. However, it proved to be combination thereof, this book will take you through Details and spotting features often This book offers a summary of standard- Chapter 11 includes diesel rosters for
among the most popular, with more change during each locomotive’s produc- gauge, heavy-duty diesel-electric models more than 120 individual railroads, includ-
than 2,700 built. These locomotives, the history of diesel locomotive evolution and guide you through tion run. These changes can be large or built by major manufacturers for use in the ing road numbers (and changes) and dates
with similar offerings from Alco small and reflect modifications to upgrade U.S., Canada, and Mexico. Builders cov- built. Most are historical summaries of
and others, soon eliminated steam the hundreds of different models and variations that have been performance, replace troublesome compo- ered include EMD, GE, Alco, Baldwin, railroads that no longer exist (mainly
locomotives from railroads across nents, cut manufacturing costs, or stan- Fairbanks-Morse, and Lima, along with through mergers, sales, or abandonment),
North America. EMD produced since the 1930s. dardize components with other models. their Canadian subsidiaries. It does not but current summaries of current Class 1
Examples include changes in grille, louver, include small industrial switchers, electric railroads are included.
and access door style or location, handrail locomotives, locomotives built for export, Railroads began rebuilding older loco-
style, window style or location, frame turbine locomotives, or experimental loco- motives in the 1950s. Several railroads
length, or cab and hood shape and style. motives (or some locomotives where only a embarked on major rebuilding programs
Other spotting features involve optional few were built). from the 1960s onward, and many inde-
components. These usually vary by railroad Chapters 5 through 9 provide a model- pendent shops provide rebuilding services
preference, and can encompass multiple by-model listing for each manufacturer, as well. Chapter 10 provides a summary of
options offered by a builder. Examples with basic spotting and identification fea- this, but the sheer number of rebuilds—not
include horn and bell (style and location), tures and information for each type. Sum- to mention the myriad new designations
fuel tank size, headlight style and location, maries for each locomotive type list the and model numbers given them—pre-
truck type, high or low nose (for first- and major buyers for each model. If space cludes providing spotting and roster infor-
second-generation hood units), and allows, all initial buyers are included; some mation for all of them.

—4— —5—
 The diesel engine
Diesel engines are built to many different
designs, but the principle of each is the
same. A series of pistons, each in a cylin-
der, move up and down and in doing so
rotate a crankshaft that runs through the
engine. Unlike a gasoline engine, which
uses a spark to ignite the fuel in each cyl-
inder, a diesel engine fires by compression.
This is done by compressing the intake air
to 500 psi or higher, whereupon it reaches
a temperature of about 1,000 degrees F. An
atomized spray of diesel fuel is then
injected and burns, propelling the piston.
Diesel engines are either four-cycle or
Dynamic
Engine Radiator fans Lube oil cooler two-cycle designs (see the following
Dynamic
Turbocharger brake grids brake fans water tank Sand box pages). A four-cycle engine completes four
Inertial air filter
piston strokes (two up, two down, produc-
Electrical cabinet
ing two driveshaft revolutions) to get one
Control stand
power stroke. The process starts with the This 1949 view of the erecting floor at EMD shows a 567 diesel engine, generator (on
Sand box intake stroke (the piston descends and the deck at the left end of the engine), and electrical cabinet (far left) in place on an
clean air is drawn into the chamber), fol- F7 frame. An FP7 is taking shape in the background. EMD
Air compressor lowed by the compression stroke (the pis-
16-645E3
Lube oil filter ton moves upward and compresses the air),
AR10A7-D14
engine power stroke (fuel is admitted and burns Exhaust
Traction generator- Fuel tank from the high temperature gained by com-
Electrical motor alternator elbow
HT-C cabinet blower pression, forcing the piston downward), Cylinder
Batteries truck air filter head
D77B traction
motor (1 of 6)
(1 of 2) and exhaust stroke (the burned gases are
discharged as the piston moves upward).
Four-cycle engines are made practical by
— C HAPTER TWO — turbocharging, which we’ll discuss in a bit.
A two-cycle engine accomplishes the Exhaust
valves

How diesel locomotives work

same tasks with just two strokes and one rev-
olution of the crankshaft, requiring the above
steps to be accomplished in much less time.
To do this, the cylinder simultaneously takes Cylinder
in clean air and expels exhaust gas on the

A
Head
This cutaway view of an EMD SD40 diesel-electric locomotive is basically an electric locomotive piston downstroke, so that on the upstroke gasket
shows how the diesel engine and the new air is being compressed and is ready Air box
other components fit together on a that carries its own portable power plant driven by a large for ignition when the piston reaches the top
locomotive platform. Rick Johnson of the cylinder.
Piston
diesel engine. The engine turns a generator or alternator, which By 1920, the diesel engine had proven
itself practical for many applications, but Cylinder
provides electricity for traction motors mounted on the axles. The engines were big, heavy, and slow. The liner Piston rod
main design challenge in reducing the size
specifics of how this is done vary by manufacturer and have and weight was that fuel has to be forced
into the cylinder at extremely high pressure Crankshaft
evolved over time, but having a basic knowledge of how diesels (to combat the pressure required for the
combustion air in the cylinder). The result-
work will help you understand why diesel locomotives are ing long fuel lines needed to build up the
pressure took up a lot of space. The break-
designed the way they are, what their strengths and limitations through came in the 1920s with the devel-
opment of injectors that could force air
are, and what the differences are among the various models. into the cylinder at the required pressure,
and do it at the cylinder.
Engines from several manufacturers
powered early railroad locomotives and This cutaway cross-section view shows an Electro-Motive Division 567 diesel engine, a
motor cars, including Ingersoll-Rand and V-style design with cylinders at a 45-degree angle. EMD

— 26 — — 27 —
SW7, TR4 SW8, TR6 SW600, SW900 SW1000

Weyerhaeuser No. 1 is an SW600. It has five slits on the

battery-box louver behind the cab—but early models had
six slits, like the SW8. Stan Mailer The SW1000 introduced a new cab design and higher-level
Rock Island No. 817 is an SW8, with a single stack and running boards. EMD
The 600-hp SW600 and 900-hp SW900 shared the same body,
Union Pacific No. 1800 is a late SW7, indicated by the eight louvered doors on the hood. EMD but had six- and eight-cylinder 567C engines, respectively. Fea- When EMD introduced the 645 engine, the 1,000-hp SW1000
straight-top cab windows. The hood has the single taper tures include a single exhaust stack and tall front grille. Early became the company’s low-horsepower switcher, using an
An eight-cylinder 567 engine bumped the SW8’s horsepower to bodies were identical to the SW8; later bodies had battery-box
at the cab of later SW-series locomotives. EMD 800 from the 600 of the SW1. The locomotive shared the same eight-cylinder version of the engine. The 645 required a taller
louvers with five slits instead of six. Few SW600s were built, hood than the 567 (and the hood was a foot narrower as well),
body as the later SW600 and SW900, but had six battery-box mostly for industrial users, as train sizes were growing and
louvers behind the cab (as did some early units of the later changing the appearance significantly. The running boards were
common-carrier railroads were looking for more powerful located noticeably higher than on earlier switchers, and the
models). The TR6 is a cow/calf version of the SW8. switching locomotives.
SW8 major buyers: ACL, B&M, CN, CP, CStPM&O, CRI&P, C&W, locomotive had a taller cab with a shallower roof radius. Op-
SW600: C&NW and 13 industrial owners tions included standard AAR type A switcher trucks or Flexicoil
DL&W, GN, LV, NYC, NKP, SP, T&P, US Army, WAB SW900 major buyers: AT&SF, B&O, BS, CN, CP, C&NW, CRI&P,
TR6: SP 4600-4603; OM 1207-1213, 1216 trucks, which allowed higher speed for road use.
GTW, LV, NYC, RR, RDG SW1000: BS, CB&Q, D&RGW, D&NE, HB&T, several industrial
owners

SW9, TR5
SW1001 SW1200

The TR4 is a cow/calf version of the SW7. Chesapeake &

Ohio No. 6000 was one of 13 sets built. EMD

The 1,200-hp SW7 has two exhaust stacks centered on the

hood roof, a large front grille that extends to the bottom of
the hood, and six rows of louvers along the hood sides with
a gap between the top and bottom sets. Early SW7s have cab The SW9 has two exhaust stacks and eight louvered hood
windows with curved tops; these became rectangular after
April 1950. Early SW7s had louvered rooftop radiator openings; doors, but lacks the upper set of louvers found on the
in mid-1950 this changed to a wire-covered opening. The TR4 is SW7. EMD
a cow/calf version of the SW7. Rock Island SW1200 No. 930 rides on Flexicoil trucks
SW7 major owners: ACL, CNJ, C&O, C&EI, C&IW, CB&Q, CRR, The SW9 was an upgraded version of the SW7. Both were
DT&I, Erie, GN, IC, IHB, KCS, LV, L&N, MEC, MP, NC&StL, NYC, NKP, rated at 1,200 hp, but the SW9 had the improved 12-cylinder The SW1001 has lower running boards than the SW1000, instead of the standard AAR type A trucks. EMD
NP, PRR, SSW, SLSF, SOU, T&P, UP, WAB 567B engine. Its appearance is similar to the SW7, but the SW9 but retains the taller hood. EJ&E No. 445 rides on AAR type
TR4: AT&SF 2418, 2419; BRC 502-506; C&O 6000, 6001; MILW lacks the upper set of louvers along the side. The SW9 also has The SW1200 was almost identical to the earlier 1,200-hp SW9,
A trucks. Tom Healey but had an upgraded 567C engine. About the only way to dif-
2001-2006 a straight edge on the trim piece at the stairwell (the SW7’s
is curved), a fifth lift ring on each side, and new engine-door ferentiate an SW1200 is by the five louvers in its battery box
The SW1001 was built at the request of industrial users who (behind the cab). The SW9 has six louvers, but so do SW1200s
latches of the same style as the GP7. The TR5 is a cow/calf ver- wanted a lower-profile switcher for clearance reasons. The
sion of the SW9. built until March 1955. Some SW1200s rode on Flexicoil trucks.
SW1001 is internally the same as the SW1000, but had a short- These locomotives had notches cut in the frame at the corner
SW9 major buyers: AN, AT&SF, ACL, B&O, B&M, CN, CG, CNJ, er cab, low-level running boards, a cab profile like the SW1200,
C&O, C&NW, CRI&P, DL&W, DM&IR, Erie, FEC, GTW, HB&T, IC, LV, steps to clear the trucks.
and two side cab windows (the SW1000 has four). The hood is Major buyers: AT&SF, B&O, BRC, CN, CP, C&IM, C&NW, CB&Q,
L&N, MP, MKT, NYC, NKP, PRR, Soo, SLSF, TRRA, T&P, UP, URR, still tall. Options included AAR type A or Flexicoil trucks.
WAB CRI&P, DL&W, D&RGW, EJ&E, FEC, GTW, GN, IT, KCT, L&N, MILW,
SW1001: BS, EJ&E, GW, G&W, KCS, LIRR, RDG, several indus- MN&S, MP, MKT, NYNH&H, NP, P&BR, PRR, RDG, RF&P, SSW, Soo,
TR5: UP 1870-1877; Union 701, 702, 703C, 704C (C units are trial users
extra calves) SP, TRRA, WAB

— 62 — — 63 —
Denver & Rio Grande Western Original road numbers
4001-4003
Second numbers Qty.
3
Model
ML-4000
Builder
Kraus-Maffei
Dates built
1961
Notes
4
1941-1988
5100-5113 14 GP7 EMD 1950-52 5
The Denver & Rio Grande Western began dieselizing with switchers and EMD FTs during World War II, but wasn’t fully dieselized until 1956. The 5200-5204 5 RS-3 Alco 1951
Rio Grande purchased Southern Pacific in 1988, but the new railroad retained the Southern Pacific name. The D&RGW initially retained much of
its identity, and received its last diesel order (GP60s that were originally part of an SP order) in 1990. 5300-5304 5 SD7 EMD 1953
5305-5314 10 SD9 EMD 1957
5315-5340 26 SD45 EMD 1967-68
Number 5305 is one of 10 SD9s purchased by
Rio Grande in 1957. EMD 5341-5413 73 SD40T-2 EMD 1974-80
5501-5517 17 SD50 EMD 1984
5901..5954 24 GP9 EMD 1955-56 6
6001, 6003, 6011, 6013 4 PA-1 Alco 1947
6002, 6012 2 PB-1 Alco 1947

Notes:
1—Ex-Sumpter Valley 101, acquired 1963 (3-foot gauge).
2—When F units (564 and below) were renumbered in 1950, a fourth digit replaced the original letter suffix: 1 for A, 2 for B, 3 for C, and 4 for D (thus 540A became 5401, 544C became 5443,
etc.). F units delivered after that were numbered in the same pattern.
3—Ex-Conrail (nee Penn Central) 3113..3169, acquired 1984.
4—Diesel-hydraulic locomotives; sold to Southern Pacific in 1964.
5—No. 5100 was originally first 5104; renumbered in 1951.
6—GP9s were numbered in a similar pattern as F units: 5901, 5902, 5903, 5904, 5911, 5912, etc., to 5954.

Published rosters:
Diesel Locomotive Rosters (Wayner Publications), Extra 2200 South, October-November 1970

Detroit & Toledo Shore Line

1950-1981
The Detroit & Toledo Shore Line dieselized with a fleet of 10 EMD GP7s and six EMD switchers from 1950-1953, and they remained the rail-
road’s standard power until the line was merged by Grand Trunk Western in 1981.

Road numbers Qty. Model Builder Dates built Notes

41-50 10 GP7 EMD 1951-53
116-118 3 SW7 EMD 1950
Original road numbers Second numbers Qty. Model Builder Dates built Notes
119-121 3 SW9 EMD 1951-52
38-43 6 44-tonner GE 1941-42
Published roster:
50 1 30-ton Davenport 1937 1
Diesel Locomotive Rosters (Wayner Publications)
66-74 9 VO660 Baldwin 1941
100 1 NW2 EMC 1941
101-119 19 S-2 Alco 1943-44
Detroit, As with most DT&I diesels, GP35 No. 353
lacks dynamic brakes. EMD

Toledo &
120-123 4 H-10-44 F-M 1948
130-139 10 SW1200 EMD 1964-65
140-149
150-152
10
3
SW1000
H-15-44
EMD
F-M
1966, 1968
1948 Ironton
540A-551A, 540D-551D 5401..5514 24 FTA EMD 1942-44 2 1941-1980
540B-551B, 540C-551C 5402..5513 24 FTB EMD 1942-44 2 The Detroit, Toledo & Ironton began buying
552A-554A, 552D-554D 5521..5544 6 F3A EMD 1946 2 diesel switchers in 1941 and road units—
EMD GP7s—in 1951, gradually adding more
552B-554B, 552C-554C 5522..5543 6 F3B EMD 1946 2 Geeps until dieselization was complete in
555A-564A, 555D-564A, 5651..5764 5551..5644 44 F7A EMD 1949-52 2 1955. The railroad owned EMD diesels exclu-
sively until it was sold to the Grand Trunk
555B-564B, 555C-564C, 5652..5753 5552..5643 42 F7B EMD 1949-52 2 Western in 1980.
5762, 5763, 5772, 5773 4 F9B EMD 1955
5771, 5774 2 F9A EMD 1955
3001-3028 28 GP30 EMD 1962-63 Original road numbers Second numbers Qty. Model Builder Dates built Notes
3029-3050 22 GP35 EMD 1964-65 200-206 7 GP38 EMD 1966, 1969 1

3051-3093 43 GP40 EMD 1966-71 210-214 5 GP38AC EMD 1970

3094-3130 37 GP40-2 EMD 1972-83 215-217 (1) 209, 208, 207 3 GP38AC EMD 1970

3131-3153 23 GP40 EMD 1968 3 215-217 (2) 3 GP38AC EMD 1971

3154-3156 3 GP60 EMD 1990 218-220 3 GP38 EMD 1971

— 206 — — 207 —