GP40, GP40-2

[sparkingbolt]

Can anyone tell me the differences between a GP40 and a GP40-2, at least visually? Thanks, Dan

[Anonymous]

Dan--

Here are the main visual differences:

1. Trucks. Most Dash 2s had high-adhesion trucks (with dampening struts).

2. Battery box covers. On Dash 2s the battery box covers were bolted on , and did not have latches or hinges. On the fireman's side, the battery box covers extended farther to the rear than those on the previous units.

3. Cab roof. The cab roof on the Dash 2 units sloped back somewhat (toward the long hood) on both sides.

4. Sight glasses. On Dash 2s, a sight glass was installed on a hood door on the engineer's side beneath the forward end of the radiator intakes to allow reading of the engine cooling water level without opening the doors.

5. Rear classification lights. On the Dash 2s, provision was made on the long hood end to mount classification lights in alternate locations (either above ar below the number indicators). Typically one of the locations had lights installed, and the other was blanked with sheet metal (although the round gasket was still in place).

--John

[sparkingbolt]

Thanks. John. I found some more info too, on SP engines at least. I didn't note any of the differences you pointed out, mainly cuz i didn't know where to look. Ill go back and look.

On SP and subsiddiary roads, the da***wo's all have a retangular box on top of the cab roof, A.C I would assume. And a retangular raised steel mesh or stamped grille over something behind the cab but forward of the fans. Thanks again, Dan.

[sparkingbolt]

PS I went to my fave prototype site, a Southern Pacific site.
http://espee.railfan.net/bullitin.html

here you can see lotsa pix of SP equipment, etc. Another detail:
I noticed that SSW's dash 2s had a brakewheel on the left side of the short hood, not there on the GP 40s
.
These were GP 40s rebuilt into dash 2s so don't reflect all the changes found on factory units. Check it out! Dan

[Anonymous]

As I understand it, the -2 designation refers to a unit with modular electrics (which I realise is unlikely to be obvious from the outside, apart from the modifications described by others)

[wp8thsub]

"On SP and subsidiary roads, the da***wo's all have a retangular box on top of the cab roof, A.C I would assume."

That's right. Some roads like WP retrofitted A/C during rebuilding programs, so that's not necessarily a -2 feature.

"And a retangular raised steel mesh or stamped grille over something behind the cab but forward of the fans."

SP/SSW units typically have a radio ground plane tower mounted above the inertial filter hatch just behind the cab. Very late -2s have the Federally mandated exhaust silencer just forward of the dynamic brake hatch (locos so equipped also have "Q" - for quiet - radiator fans, which are of a different shape from the earlier type, and often have angled grabs behind the rear radiator fan).

In addition to those mentioned above, -2s have more detail differences from "straight" GP40s (not all inclusive):

* Inertial filter intake grilles and hatch shapes.
* Dynamic brake housing shapes and vents.
* Number and arrangement of hood doors.
* Nose length (81" vs 88" standard varies with date of production).
* Radiator grilles.
* Electrical cabinet air filter box on fireman's side behind cab.
* Seam on carbody near inertial filter cabinet.
* Additional knockout locations (not alternate class light locations) near the top of the long hood end)
* Ribs on traction motor blower bulge.
* Anticlimbers on late units.
* Plus more no doubt, most of my research stuff is in storage so I can't get to it easily...