Locomotive Descriptions and Phases - EMD / GMD F40PH series
The F40PH was introduced in 1976, with specifications initially drawn up by Amtrak Manager of Locomotive Development Deane Ellsworth. In contrast to the six-axle cowl passenger units built in the previous decade (such as the FP45, SDP40F and F40C) the F40PH was a shorter 4-axle design. It adopted most of the mechanical components from the EMD GP40-2, including the 3,000-horsepower 16-cylinder 645 series engine, AR10 main alternator and single-shoe swing-hanger "Blomberg M" trucks.
Externally, the F40PH was easily identified by the simple sloped and tapered nose with no front platform, trapezoidal windshields, and angular full-width carbody with three radiator fans at the rear (and, if present, smaller dynamic brake intakes with a single fan in the middle). While previous EMD cowl units used three rows of wide horizontal panels on the carbody sides, the F40PH used narrower full-height panels, which were retained on several later EMD passenger models.
The relatively short frame (56' 2" over the coupler pulling faces) left insufficient room for either a steam generator (by that point obsolete) or a separate head-end power (HEP) engine and generator, so the F40PH generated HEP with an alternator connected directly to the prime mover, located in the rear of the carbody between the accessory rack and air compressor. This arrangement required the prime mover to run at full speed (900 rpm) to generate HEP at 60 Hz, with power to the traction motors controlled by varying the main alternator excitation. An alternative "standby" mode allowed the production of HEP alone at a reduced engine speed of 720 rpm. Power required for HEP therefore resulted in a corresponding decrease in power available for traction. When HEP was not in use, the engine loading could be changed to vary the engine speed in each throttle notch, as on a freight unit; on trains with more than one locomotive, this setting was often used for the lead units to reduce noise and fuel consumption, with only the rear-most unit providing HEP.
Initially intended as a short-distance or corridor locomotive, the F40PH ultimately became the backbone of the Amtrak fleet from the late 1970s to the late 1990s. A spate of derailments with Amtrak's earlier long-distance SDP40F locomotives shook their confidence in the design, and most were traded in for components to be reused in F40PH construction. While Amtrak owned the largest fleet of F40PH's, the model found favor with other passenger and commuter operators, where several model variations would end up remaining in service decades after Amtrak had retired theirs.
Phases
In railfan and modeling circles, the F40PH is commonly divided into phases 1, 2a, 2b and 3, describing variations in the fuel tank location, rear carbody ribs and radiator fans. While these phases are accurate, they're incomplete - there were many other small changes that occured, mostly during Phase 3 production. I've elected to divide Phase 3 into four subphases; the divisions were a bit of a challenge as several details were either inconsistent or retrofitted to earlier units.
These phases apply to EMD production. Later units built under license by MK / MPI are not included in this table but generally had Phase 3c spotting features.
| Phase | 1 | 2a | 2b | 3a1 | 3a2 | 3b | 3c |
|---|---|---|---|---|---|---|---|
| Dates | 1976-03 - 1977-12 | 1977-07 - 1978-05 | 1978-03 - 1979-10 | 1979-11 - 1981-12 | 1983-02 - 1983-05 | 1985-03 - 1985-08 | 1986-11 - 1992-12 |
| Production | AMTK 200-229 (F40PH) RTA 100-127 (F40PH) | AMTK 230-269 (F40PHR) AMTK 270-279 (F40PH) GOT 510-515 (GMD F40PH) | AMTK 300-309 (F40PH) AMTK 280-299, 310-328 (F40PHR) MBTA 1000-1012 (F40PH) | AMTK 332-359 (F40PH) AMTK 329-331, 360-390 (F40PHR) MBTA 1013-1017 (F40PH) NJTR 4113-4129 (F40PH) RTA 128-149 (F40PH) | RTA 150-173 (F40PH-2) | AMTK 391-400 (F40PHR) CDTX 900-917 (F40PH-2) | AMTK 401-409 (F40PHR) CDTX 918-919 (F40PH-2) MBTA 1050-1075 (F40PH-2C) METX 174-184 (F40PH-2) METX 185-214 (F40PHM-2) VIA 6400-6458 (GMD F40PH-2D) |
| Underframe | Air reservoirs at front, battery boxes in middle, fuel tank at rear | Fuel tank at front, battery boxes and air reservoirs at rear (except F40PH-2C and GMD F40PH-2D) | |||||
| Rear carbody | 3 ribs | 4 ribs | |||||
| Radiator fans | Flat-top | Q-type | |||||
| Truck wheel bearings | Hyatt cylindrical oil | Timken tapered grease (except AMTK 391-400) | |||||
| Left air piping | Revised support locations, 180-degree bend moved approx. 15" rearward | ||||||
| Phase | 1 | 2a | 2b | 3a1 | 3a2 | 3b | 3c |
| Right air piping | 924-series dryer | 975-series dryer (most units), revised piping (varied between orders) | |||||
| Air reservoir supports | C-shaped bracket attached to upside-down U-shaped support | L bracket suspended from U-shaped support | |||||
| Exhaust silencer | Opening at rear | Opening at front (retrofitted to many earlier units) | |||||
| Cab door window | Square corners | Rounded corners (except METX units) | |||||
| Fuel vent pipe | Approx. 2.25" outer diameter, sharp 90-degree bend | Approx. 2.75" OD, broader curve | |||||
Hood louversLouvers on upper hood side below exhaust stack on units equipped with dynamic brakes
| Single row of 4 louvers (retained on VIA 6400-6429) | 2 rows of 6 louvers (appeared on AMTK 329-390) | |||||
| Phase | 1 | 2a | 2b | 3a1 | 3a2 | 3b | 3c |
Model Variations
From the original F40PH design, EMD spun off a number of model variations. Further details are described under "Railroad Variations" further down.
F40PHR: Built for Amtrak using components from traded-in SDP40F units. Mechanically and visually the same as a standard F40PH.
F40PH-2: Evolution of the F40PH built after 1982; some (or all) were rated at 3,200 hp. Built for Caltrain and Metra.
F40PHM-2: A single order of 30 units built for Metra in 1992 with a larger cab with sloped windshields moved to the front; otherwise similar to previous F40PH-2 units
F40PH-2M: Four units built for Speno for rail-grinding service without turbochargers or HEP. A larger cab had standard F40PH windshields moved to the front (later replaced with a new cab altogether)
F40PH-2C: Lengthened by 8' 1" to make room for a separate HEP generator at the rear. Built for MBTA by EMD in 1987-88, then for several roads under license by MK / MPI after 1990.
F40PH-3C: Similar to the F40PH-2C but with microprocessor controls. Built for ACEX by MPI from 1997 to 2006.
F40PH-2D: Built by GMD for VIA Rail; similar carbody but different arrangement of fuel tank / air reservoirs / battery boxes. "D" was for desktop controls.
Railroad Variations
Amtrak
Other than the significant change from Phase 1 to 2a, Amtrak's units were remarkably consistent over their 12-year production run. Owing to clearance restrictions, all the rooftop components were of a low profile, including the horn (recessed into a notch at the front), inertial air system hatch and radiator fans (later Q-fans were recessed approx. 2.5" into a lowered roof panel). The cab roof had a large blank plate in the middle (provision for air conditioner installation) behind which were a vent and radio antenna. A single red strobe was mounted on the front of the cab between the numberboards, and two white strobes were mounted at the front top corners above the windshields. Standard EMD classification lights were at the cab and hood upper ends, and the top of the short hood had gribirons along the front edge not used on other roads.
Of the 210 purchased new by Amtrak, 132 were built using components from retired SDP40F's. They were visually identical to their all-new counterparts and were commonly referred to as "F40PHR" - which I believe is an Amtrak "on-paper" designation as the EMD documents and builder's plates I've found still say "F40PH".
Under the frame, the front pilot had a large plow, and the rear pilot had a partial end plate with MU hose pockets (the latter was standard across most F40PH production). AMTK 200-328 were built with EMD's standard single-shoe swing-hanger "Blomberg M" truck, with earlier units using trade-in LFM castings and later units using new Rockwell castings. Starting with AMTK 329, a modified version of the truck replaced the secondary suspension "sandwich" of rubber pads with inclined "chevron" rubber pads, angled inward and outward below the bolster. The revised suspension was an attempt to restore some of the compliance of the leaf spring used in earlier clasp-brake versions of the truck.
Among his other work at Amtrak, Deane Ellsworth is also credited with suggesting chords for several new horn types. After the Leslie SL-4T and Nathan P5a (used on earlier Amtrak units) he approached Bob Swanson of Airchime to modify the K5H already in service on Canadian railroads. By boring out the throat of the #3 and #4 bells to lower the pitch, the tuning was changed from a D# minor sixth (D#, F#, A#, C, D#) to a B major sixth (D#, F#, G#, B, D#), and the bells were mounted in an arc on a lower-profile manifold to fit Amtrak's clearance restrictions. The resulting K5LA horn went on to become the most common 5-chime horn in North America, and appeared on all Amtrak F40PH's after the first order. While originally designed for Amtrak, the first production K5LA's were fitted to an order of SD40-2's delivered in early 1977 to Chessie System (where Ellsworth had worked previously).
During their roughly two decades of service on Amtrak, the units received a number of modifications:
Carbody and roof
- Lights: The two white strobes were initially Whelen units (possibly also models from Federal Signal) but were swapped out for Star 200BC strobes (with a clear dome over the strobe) around the late 1980s. On some units the classification lights were replaced with forward-facing red marker lights. Ditch lights were added in the bottom corners of the short hood on most units in the 1990s.
- Cab: An air conditioner was installed in the blank plate on the cab roof. The side windows (and in many cases the windshields) were modified with thicker metal perimeter in place of the original nearly flush gasket.
- Carbody: The side steps were recessed in place of being flush-mounted. Some units had the side doors replaced with the later version with rounded window corners.
- Exhaust: The original silencer design had two elbows that located the exhaust opening at the rear. Many (possibly all) units were retrofitted with the updated silencer design that appeared in 1985, with the opening at the front (directly above the turbocharger).
Underframe
- Trucks: Hyatt oil bearings (used on almost all units as-built) were swapped out for Timken sealed bearings with exposed end caps.
- HEP Connections: As built, AMTK 200-390 had HEP receptacles at the upper corners of the pilots. These were replaced with cables with plugs at the same location, and receptacles lower down on the pilots; this arrangement was present on AMTK 391-409 as built.
- Air piping: AMTK 200-390 were originally equipped with a 924 series air dryer ahead of the air reservoirs. Most units received an additional 824 air filter just behind the dryer, and a few units had altered piping to accommodate a 975 series dryer (present on AMTK 391-409).
- Fuel tank: The first order (AMTK 200-229) was originally built with a 1500-gallon fuel tank; this was later extended forward to match the size of later units (1800 gallons).
- Fuel filler: All units were originally equipped with three fuel fillers of various types. In most cases, two of the three were later plugged, with only the standard Snyder connector remaining (identified by three tabs on the filler cap).
▼ Illustrations (AMTK #230-279, Phase 2a)
Go Transit
The F40PH didn't take off immediately in Canada. Initially, the only Canadian order was for six units for GO Transit, built by GMD in London and numbered 510-515. They had Phase 2a spotting features and were quite similar to concurrent Amtrak units, with the biggest difference being the absence of dynamic brakes. Other changes were relatively minor and were typical of either Canadian railroad specifications or GMD construction, including the use of a large Pyle headlight, Dofasco truck castings, bottom-operated coupler cut levers, a cab-mounted bell, and triple separate classification lights. Although GO Transit was not subject to the same clearance restrictions as Amtrak, they retained the same notch for the horn (with a K5LA) and low-clearance inertial air system hatch and radiator fans.
In 1990, as GO Transit standardized on the F59PH built to their own specifications, the F40PH's were sold to Amtrak and numbered AMTK 410-415. They had dynamic brakes retrofitted (with a shorter intake with narrower bar spacing compared to units as-built) along with a number of other Amtrak-specific modifications, including the addition of a plow, top-operated couplers, revised air and HEP connections, and all the updates Amtrak made to their own units in the 1990s (such as air conditioning, ditch lights and recessed side steps). After retirement from Amtrak, one unit (411) would find its way back to Canada for use on the AMT in Montreal; one (413) was rebuilt by Amtrak as an NPCU (non-powered cab unit); and one (415) would end up on the Panama Canal Railway.
RTA / Metra
After Amtrak, Chicago's Regional Transportation Authority (rebranded as Metra in 1985) had the second-largest F40PH fleet, ultimately amassing a total of 115. The first order (RTA #100-127, built 1977) had Phase 1 spotting features while the last units (F40PHM-2's #185-214, built 1992) were both the last F40-series units built by EMD and the last locomotives manufactured at EMD's LaGrange locomotive plant.
While there is occasionally some confusion about the model names for Metra's units, EMD operator manuals and parts catalogs list the model as F40PH for #100-149, F40PH-2 for #150-184, and F40PHM-2 for #185-214.
Despite the long production span, RTA / Metra units had fairly consistent specifications:
- Gyralite with clear / red lenses between the numberboards
- Amber beacon on the cab roof (not initially present on the earliest RTA units)
- Red marker lights on the corners of the short hood
- Nathan P5a horn with #4 bell reversed
- Sloped front pilots with bottom-operated Type F couplers
- Rear platforms with single bottom step and no handrails
- Speed recorders on the #1 and #3 left-side axles; ATS shoe (not always present) on the #2 right-side axle
There were a few variations between orders. RTA #128-149 had square jacking pads with 4 small holes, like those used on some contemporary LIRR and SP units. RTA #150 and later units had a larger fuel tank (2000 instead of 1800 gallons) along with double surface-mounted cab sub-base panels in place of the standard single flush panels; these were later retrofitted to earlier units. F40PHM-2's #185-214 lacked class lights and had ditch lights as-built, in addition to being the most visually distinct with large forward-mounted sloped windshields.
Metra's units received a number of modifications while in service:
- Addition of ditch lights (mid-late 1990s)
- Removal of class lights (mid 1990s - mid 2000s)
- Addition of oblong vents under cab side windows and grabirons above windshields (mid-late 1990s)
- Addition of Coleman RV-style air conditioners on cab roof (late 1990s - early 2000s)
- 2-step cab ladders replaced with taller 3-step ladders (2000s)
- Addition of vertical / angled grabiron on outer edges of rear carbody end (not all units)
Beginning in 2009, Metra's F40PH fleet underwent rebuilding as "F40PH-3" units by Progress Rail, with #100-127 rebuilt in 2009-2011 and #128-149 in 2011-2012. Internally, they retained the same prime mover and HEP system but with remanufactured components and a new microprocessor control system.
Externally, the most significant update was the reconfigured underframe components, with a larger fuel tank mounted at the rear, battery boxes moved ahead of the fuel tank, and horizontal lengthwise air reservoirs above the fuel tank in place of crosswise tanks below the frame. The units initially received a fresh version of the blue and orange paint they had prior to rebuilding.
Other changes included:
- New cab side doors and door frame, with a small rounded square window (in place of rectangular window)
- Cab side windows with metal perimeter around gasket
- Recessed cab side steps (like those on F40PHM-2)
- Slightly smaller hood side access doors under radiators (left side) and dynamic brakes (right side)
- Top-operated Type F couplers with new uncoupling levers
- Medium-sized front plow in place of sloped pilot
- Revised speed recorder on #3 axle
In 2016-2017, the last batches of Metra units (F40PH-2's #174-184 and F40PHM-2's #185-214) underwent similar rebuilds, except they retained their original fuel tank and air reservoirs. They emerged with Metra's newer paint scheme with a blue-to-silver gradation.
Other than #173, F40PH-2's #150-173 were not rebuilt like the rest of the fleet, and units in this series were the first to be retired or stored starting around 2022.
▼ Illustrations (METX #185-214)
VIA Rail
In what would become one of the most successful applications of the model, VIA Rail took delivery of 59 F40PH-2D units in three batches from 1986 to 1989. They became the mainstay of the VIA Rail long-distance fleet, replacing venerable MLW FPA-4's and most remaining GMD F-units. While they retained some of the superficial Canadian details of the GO Transit units (large Pyle headlights, triple classification lights, Dofasco truck castings, bottom-operated couplers) their design also took some more notable departures from the initial EMD version, including the use of a desktop control stand (hence the "D" in the name). Mechanically, they were largely the same as other F40PH-2 units, but unlike on Amtrak, VIA's rolling stock had parallel HEP lines that allowed two units to provide simultaneous unsynchronized HEP (one down each side of the train).
Externally, the most obvious difference from the standard F40PH was the relocation of the battery boxes to immediately behind the front truck, which moved the fuel tank and carbody side door rearward. The fuel tank had taller sides, and slightly longer / narrower air reservoirs were placed behind it. On the roofline, the inertial air system hatch, dynamic brake fan and radiator fans were all standard-height (taller), and the forward radiator fan was covered with a winterization hatch. Several other minor details were unique to the VIA Rail design, including the sub-base doors, ditch lights below the anticlimber, side ladders and recessed steps, and some of the underframe pipe and cable routing. The horn was an Airchime K3H, typical of most Canadian locomotives.
Over the years they received a number of minor changes, including:
- Removal of sand lines
- Addition of air conditioning
- Wind deflector added to the short hood
- Insulation over portions of the air piping and fuel tank vent pipe
- Inertial air intake changed from corrugated screen to an array of smaller rectangular filters
In 2006, a single unit (6400) received a rebuild with updated control systems and new/refurbished components, but no major external changes. From 2009 to 2012, all the remaining units underwent a significant rebuild at CAD Industries, with the biggest change being the addition of a separate HEP generator in an extension of the rear hood occupying the rear platform. In addition to providing maintenance and fuel savings, the separate HEP unit freed up the power of the original prime mover to be used entirely for traction. The existing carbody and main mechanical components were refurbished, and significant upgrades came to the control systems and electronics, including microprocessor controls, all new piping and wiring, electronic fuel monitoring, braking and engine governor, and ergonomic improvements to the cab. The sand hatches and access panels were plated over, a third high-intensity central front headlight was added, and a K5CA-LS emergency horn was added to the cab roob (split across two manifolds). After rebuild, the model designation remained "F40PH-2D", but they were released in a new "Renaissance" paint scheme similar to VIA's GE P42DC units.
In 2024, VIA announced the intent to rebuild most of the remaining fleet a second time with the goal of keeping them in service until 2035, which would bring their service life to nearly 50 years.
▼ Illustrations (VIA #6430-6458)
As built - As modified - As rebuilt
References
Canadian Public Transit Discussion Board. (2025). Metra 100-184. Retrieved December 2025 from https://cptdb.ca/wiki/index.php/Metra_100-184
Donnelly, M & Stroshane, A. (2024). EMD F40PH Masterclass. Retrieved February 2025 from https://rapidotrains.com/emd-f40ph-master-class
Electro-Motive Division. (1978). Replacement Parts Catalog No. 190, General Purpose and Special Duty Locomotives.
Electro-Motive Division. (1981). Parts List No. D1511, Truck Assembly.
Electro-Motive Division. (1988). Replacement Parts Catalog No. 192, Passenger Locomotives Delivered After 1980.
Electro-Motive Division. (1992). F40PHM-2 Metra Railroad No. 610 Service Parts Catalog.
Five Chime Consultants. Airchime K5LA.. Retrieved February 2025 from http://atsf.railfan.net/airhorns/k5la.html
GM Locomotive Group. (1990). F40PH-2 Operator's Manual, 3rd Edition.
King, S. (2002). Strobes - Gyrating Warning Lights. Retrieved February 2025 from http://www.trainweb.org/gyra/strobe.htm
Vantuono, W. C. (2016). F40PH-3s riding Metra rails. Railway Age. Retrieved December 2025 from https://www.railwayage.com/passenger/commuterregional/f40ph-3s-riding-metra-rails/
Sarbutt, G. (2008). Amtrak Locomotive and Car Notes. Retrieved February 2025 from Web Archive version of http://www.gobytrain.us/amtrak/notes/
Trainorders.com. (2005). F40 vs SDP45. Messages posted to https://www.trainorders.com/discussion/read.php?4,1062258
Trainorders.com. (2020). K5LA Airchime by Nathan Manufacturing, Inc, 1979 -- Bill Howe. Messages posted to https://www.trainorders.com/discussion/read.php?11,5119413
Unofficial EMD Homepage. (2002). F40PH Order Numbers. Retrieved February 2025 from http://www.trainweb.org/emdloco/f40ph.htm
VIA Rail. (2009). VIA receives first environmentally enhanced F-40 locomotive from CAD Railway Industries. Retrieved February 2025 from https://media.viarail.ca/en/press-releases/2009/16-july-2009-via-receives-first-environmentally-enhanced