That's why I have been postponing it!
I tried to grind away enough of the GP40 frame to fit a speaker, but after cutting away to the point that I was comfortable with, it still would not fit. That was why I started buying the sound version of the GP38 and GP40 and swaping shells to get the road numbers. They re-designed the frame to accept the speaker and the rest stayed the same. You can try, but you will first need the smallest speaker you can find, then a really good deburring bit and a lot of patience and luck.
Just my $.02.
I have a couple Bachmann GP-38-2s that I want to add sound to, but as you said, no room for a speaker. I can make room, but it's going to require some serious grinding on the weight. Not fun. Been postponing it for two years now. Maybe this will be the year. Here is a good video on the Bachmann GP 38-2 adding sound. The guy mentions making room for the speaker, but doesn't show much of doing it. https://www.youtube.com/watch?v=IHvK6JEjNqQ
I was able to make the swap with only needing one modification to the older shells. It seems there are 4 small tabs in the inside top of the older shells, my guess is they are for light bars or something. They prevented the new frames from going all the way into the older shells. A pair of needle nose pliers and a few quick twists removed the tabs and the shells went on just fine. Now I have an Alaska GP38 with sound, road number 2007 and 4 Alaska GP40's with road numbers 3002, 3015, 3018 and 3019, all sound equipped! Happy camper.
As a matter of fact, the older shells will fit on the frames for both the new style GP40 with sound and the new style GP38 with sound.
I could probably find more GP38 shells with different road numbers, but since I now have 1 Bachmann GP38, 4 Bachmann GP40's, 3 Bowser F7's, and 3 Athearn SD70MAC's, all Alaska, all different road numbers and all with sound, I think I have more than enough Alaska diesels for the size of my layout.
They are the same. The shells are interchangable.
But, you'll notice the newer shells are higher quality.
Charles
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Modeling the Santa Fe & Pennsylvania in HO
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Can't seem to open it. Need permissions.
Maybe this diagram will help. http://www.hoseeker.net/assemblyexplosionbachmann/bachmannemdgp40pg02.jpg
Actually, I did find a phone number for Bachmann that got me through to a person in Customer Service (3 other numbers just got elevator music forever). She did not know for sure, but she compared the two locomotives and the shells looked the same and had the mounting screws in the same locations, but I already knew that much from comparing my two locomotives. She took my phone number and is trying to find a person who may know for sure. They have shells for $22.00, and have 2 different road numbers, but they are for the old GP40's and I already have 1 of the road numbers. This evening I plan to just remove the shells and find out. If they are interchangible, I can buy one shell from them with the road number I don't have and construct a 3 locomotive consist, 2 with sound units and 1 without, all different numbers, assuming I can speed match the old locos with the new locos. The two new locos are speed matched almost perfectly out of the box and the old locos are much slower than the new ones. Not sure where CV2-5-6 are set right now on either. If not, I will probably just get 1 more sound loco and change the shell, and sell off all the non-sound locos. If the 3 sound locos are too loud, I can just turn off the sound to one or both and still have 3 speed matched locos.
Can't answer the specific Q about the Bach, but you might be able to find the parts diagram on the web for both versions.
Having swapped shells on various locos from various manufacturers, I can say they generally don't do a wholesale redesign of the innards very often.
If one vintage shell wont fit directly on a later vintage, its usually due to the way the light pipes interfere with the weights. The lights might be relocated a few centimeters here or there.
Its usually not a difficult fix to modify light pipes, or shave off little nubbies that might be left over from previous fitment methods.
- Douglas
B. Bryce Same question is on their forum. Not sure how to call Bachmann and get someone to answer the phone.
Same question is on their forum. Not sure how to call Bachmann and get someone to answer the phone.
Did you try asking Bachmann directly?
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
A long time back I purchased 4 Bachmann GP40 DCC equipped/no sound locomotives. I tried to add sound to one of them, but there was no way to install the speaker without almost completely removing all the metal from the frame. Now Bachmann has released a new version of the Alaska GP40 with sound, but they only have one road number. I have three options: 1) use them as is with duplicate road numbers on the layout. 2) try to change the road number with a matching font/size/color decal if I can find one or 3) swap the shells. Does anyone know if the new GP40 shell is interchangable with the older GP40 shell? I'm hoping they kept the same shell design and only modified the shape of the frame to accept a speaker, but who knows?