Need Help: Athearn SD40-2 Parts Diagram

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#1
My question is about the Athearn SD40-2 manufactured between new tooling style and the Blue Box days. I already have an SD40-2 so I know what I need but don't know the part number. I have already discovered that the shell from that style will not fit on the new tooling frame.
I am trying to find out what the part numbers are for both the front and rear power trucks, the complete assemblies.
I have the parts diagram but unfortunately I am not home where the diagram is and I don't want my significant other to be digging through my stuff; she might start considering me to having a slight problem with hoarding.
I tried the HOseeker site but the site only hosts the Blue Box diagrams, but I did find an SD40 with the transition tooling and the truck type that I need. And I also searched through the Athearn site as well as through their parts inventory list for the parts but was unsuccessful.
If you know where the links are to the parts diagrams or if you know the parts number for the trucks, I'd really appreciate your help on this.

Thanks
And again Merry XMAS
 

Rico

BN Modeller
#2
Looks like the front is 44011 and the rear is 44012.
Hope that helps?
If the loco runs opposite to others you have them backwards by the way.:p
 
#3
Looks like the front is 44011 and the rear is 44012.
Hope that helps?
If the loco runs opposite to others you have them backwards by the way.:p
Thanks but this diagram is for a blue box. The trucks I am looking for have wires connected directly to the top of the truck as the transition type includes that for the DCC Ready sticker. I feel the trucks are similar to the part numbers you listed but have metal tabs sticking up on both sides of the truck for needling the wires through which are then secured by those plastic jumper-type fasteners. I don't care too much for the 44011 or 44012 as not having a direct electrical connection to the track.
I was able to find a parts diagram from an SD40 but evidently the trucks are different in being millimeters too short.
 
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#4
The diagram that Rico supplied IS the transition RTR SD40-2.

There are three and a half different SD40-2 models made by Athearn.

1. Blue Box which had all friction contact electricals, metal handrails, universal joints in the drive, and sintered iron wheels.

2. Early RTR (which can be considered "transitional") had all friction contact electricals, plastic handrails on a bluebox shell, hex drive shafts, and sintered iron wheels.

3. Current RTR has a new shell, same frame, wired connections, plastic handrails mounted at correct locations, hex drive shafts, Nickel-Silver wheels, and a DCC-Quick Plug light board.

3.5 RTR Canadian National SD40-2 is the same as the current RTR except it has dummy ditch lights.

If you're looking for #3, then here is the diagram:
 
#5
Thanks for your most helpful parts diagram. The part containing the gears I'll need to re-power my BNSF SD40-2 #7835 [ATH80174] is #40074. Fortunately I bought a Maersk SD40-2 in hopes that I could switch shells with my BNSF SD40-2 #6821. It didn't work as the frame is the transitional type (or it even might be a plain Blue Box) and the shell was screwed on differently. After cannibalizing the Maersk, all that will be left of that $99 learning experience is the cool blue shell and the frame.
 
#6
The frames are indeed different, but the gears are the same. The trucks may be different, and the wheels are made of different materials.

If it says DCC Quick-Plug Equipped, it should be the current model.

Your BNSF model is the transitional model. I'd cannibalize the BNSF and not the Maersk :D
 
#7
The frames are indeed different, but the gears are the same. The trucks may be different, and the wheels are made of different materials.

If it says DCC Quick-Plug Equipped, it should be the current model.

Your BNSF model is the transitional model. I'd cannibalize the BNSF and not the Maersk :D
It is the transitional model, equipped with the ancient DCC Quick-Plug; it doesn't have the large weights on top of the frame. That is why I bought the Maersk in hopes that I could just switch over the shells. The transitional model is much too light; I rationalize it as that the big void in the rear of the shell would fit a speaker perfectly.
 
#8
The BNSF shouldn't have a DCC Quick-Plug board. If it does, then it was added on later by someone else. They're not ancient, they are made by Digitrax and actually work quite well.
 
#9
The BNSF shouldn't have a DCC Quick-Plug board. If it does, then it was added on later by someone else. They're not ancient, they are made by Digitrax and actually work quite well.
When I wrote ancient, I meant the light board has this big resistor on both ends under the board. Other than not having the weights and having that big light bulb common in the blue box locomotives, I was able to swap out the light board and motor/drive shafts from the RTR Masrsk into the BNSF; the shells were different.
 





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