Last updated February 03, 2008
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Trainiax --> Drawings --> Locomotive Phases --> 4-axle EMD Locomotives
Trainiax --> Info --> Locomotive Phases --> 4-axle EMD Locomotives
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| Locomotive Phases | 4-axle EMD Locomotives |
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GP35
Phase 1a1: 7 latched hood doors, short central air intake, 6 louvers on battery boxes, flat dustbin hatch (roof behind cab), flat panel under front headlight, early (barred) radiator intakes, "fishbelly" frame
Phase 1a2: 3 latched hood doors
Phase 1b1: Longer central air intake
Phase 1b2: 7 latched hood doors, bulge under front headlight
Phase 1b3: 2 louvers on left battery box
Phase 1c: late (screened) radiator intakes, 2 louvers on both battery boxes (late Phase 1c)
Phase 1d: raised dustbin hatch
Phase 2a: flat dustbin hatch, straight frame (see resulting differences under "other details" below)
Phase 2b: raised dustbin hatch
Phase 2c: corrugated central air intake

Other details:
--The central radiator fan (36") varies between a flat open-top and a round button-top design.
--The change from a fishbelly frame to a straight frame on Phase 2a GP35's caused several visible differences, including a thinner side frame (especially above the air reservoirs), a taller fuel tank, a marginally higher walkway and new steps.
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GP38, GP40
 
Phase Built Batt. box Short hood   
grabirons		 Pilot end 
plate		 Fans ECAFB Radiator 
subscreen		 Blower 
Duct		 Dyn.brake 
taper		 Handrail  
stanchions
1a 1965.11 - 
1966.04		 Flat Top-mount   
straight		 Version 1 Flat center 
cap		 No Diamond   
mesh		 Flat Short,  
angled		 Uneven  
spacing and  
length
1b 1966.04 - 
1967.09 		 Ribbed " " " " " " " "
2a1 1967.07 - 
1967.10		 " " Some 
Version 2		 Some 
open-top		 " " " " "
2a2 1967.09 - 
1968.02		 " " Version 2 Open top Yes " " " "
2a3 1968.02 - 
1968.06		 " Bottom-mount   
drop		 " " " " " " "
2b 1968.06 - 
1971.04		 " " " " " Square  
wire grid		 " " "
2c 1971.04 - 
1971.12		 " " " " " " Ribbed Long,  
straighter 
(GP40)		 Bottom  
lined up, 4'  
even spacing
Batt. box: Battery box cover under cab
ECAFB: Electrical cabinet air filter box (behind cab, left side)
Dyn. brake taper: Front section of taper of dynamic brake intake

Other details
- Taller step spacing introduced with Version 2 pilot end plate; narrow spacing retained on some subsequent units.
- Standard fan arrangement: high radiator fans, low dynamic brake fan.  Some units had low radiator fans or dynamic brake fan raised on a rim.
- Multiple fuel tank sizes available: 2600-, 3000-, 3200- and 3600 gallon.
- Sanding nozzles: either curved under or threaded through brake shoe support.
- ECAFB retrofitted to many earlier units.
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From late non Dash-2 to early Dash-2:
--Bolted (rather than hinged) front battery boxes
--Oblong water-level sight glass (right rear of hood)
--Optional M-type Blomberg trucks
--Modified central air intake and blower duct
--Modified rear hood doors
--Lengthened walkway blower duct
--Bolted, rectangular cab side panel
--Stanchions reverted to uneven spacing (closer at rear)
--Larger ECAFB
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GP38-2
Phase 1a: long chickenwire radiator intakes, 81" short hood, older steps, bolted front battery boxes, bolted cab side panel
Phase 1b: short chickenwire radiator intakes
Phase 1c: corrugated radiator intakes, flush exhaust stacks
Phase 2a: 88" short hood, new steps, new battery box hinges,
Phase 2b: welded cab side panel
Phase 2c: Q-type fans, hinged front battery boxes
Phase 3a: straight frame profile
Phase 3b: new blower duct
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GP40-2
 
Phase 1 - 1972.04 - 1975.05
-Battery box in front of cab: bolted, small louvers
-Battery box under cab: hinged
-ECAFB: Separated from cab
-Steps: Version 1
-Radiator intakes: square wire grid
-Short hood: 81" length
-Cab side panel: bolted, 11 bolts along top/bottom
-Pilot/ends: straight upper end plate corners, no raised coupler cut lever, no front anticlimber
-Rear upper pilot/drop step area: Version 1, inward-facing handrail stanchion supports
-Radiator fans: flat top
-Exhaust: raised stack
-Blower duct: flat, wide, two ribs, no raised walkway
-Frame side sill: narrow over air reservoirs, wide at ends

Phase 2a - 1976.01 - 1978.12
-Battery box in front of cab: bolted, large louvers
-Battery box under cab: lift-off tabs
-ECAFB: Flush with cab
-Steps: Version 2
-Radiator intakes: corrugated
-Short hood: 88" length, vent on right side
-Cab side panel: bolted, 13 bolts along top/bottom
-Pilot/ends: notched upper end plate corners, raised coupler cut lever, front anticlimber (2 versions, depending on railroad)
-Rear upper pilot/drop step area: Version 2, outward-facing handrail stanchion supports

Phase 2b - 1979.01 - 1979.11
-Cab side panel: welded

Phase 2c - 1979.12 - 1981.03
-Battery box in front of cab: horizontal rib added (some railroads)
-Radiator fans: Q-type
-Exhaust: raised silencer, opening at rear

Phase 2d - 1981.05 - 1982.07
-Short hood: bolted hatch added on top

Phase 3 - 1983.03 - 1986.12
-Battery box in front of cab: latched, lift-off tabs
-Blower duct: angled, narrow, no ribs, raised walkway ("laundry chute")
-Exhaust: raised silencer, opening at front
-Frame side sill: narrow over entire length

Notes
-ECAFB: Electrical cabinet air filter box (behind cab, left side)

Other details
-Various as-built pilot options: standard footboards (up to 1975), plow (various sizes), sloped (2 types)
-Two variations in step spacing, depending on railroad
-Oblong cab vent appears on most units (generally on left side, towards rear) starting with Phase 2a
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GP38-2W, GP40-2W
Details consistent with Phase 1b GP38-2 and Phase 1 GP40-2.

Other details:
--Late GP40-2W and GP40-2LW units have a longer electrical cabinet on left behind cab, and a single louvered door at hood rear (replacing short door with bolted panel underneath).
--Late GP40-2W units have chamfered (rather than rounded) step edges.
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GP60
Phase 1: Rounded dynamic brake intake, raised handbrake wheel (if equipped), 7 latched center hood doors, 5 latched rear hood doors, high-mounted stepwell lights
Phase 2a: Squared-off dynamic brake intake, latched hatch on right side of dynamic brakes
Phase 2b: Bolted hatch on right side of dynamic brakes, 5 latched center hood doors, 4 latched rear hood doors, low-mounted stepwell lights
Phase 2c: Recessed handbrake wheel (if equipped)
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Michael Eby 2008