# Athearn SD40(blue box) mated to a Bachmann SD 40 chassis



## Andreash (Dec 30, 2018)

I while back I had acquired a Athearn sd40 in the Santa Fe Kodachrome livery. 







I wasn’t 100% sold on its performance, and recently picked up a Bachmann SD 40. Well, last night I removed the Athearn shell and it fit on the Bachmann chassis. I had to remove some metal along the top of the weight, and removed some of the chassis in the front, and rear. I removed the Bachmann dcc decoder, and used the digitrax decoder from the Athearn install. Once everything was soldered and tidied up, the shell was placed on top. It’s a tight fit, and stays on. I had to rework the coupler assemblies. It runs much better. 
On a side note, the Bachmann shell fits very well on the Athearn chassis. I stripped down the chassis (removed the motor, and made the trucks free rolling), and I’ll eventually make this engine a dummy with sound.
The photo shows the Athearn shell with the modified chassis, and the other chassis is a stock chassis (no modifications). I stripped out the Bachmann dcc board and its in a parts box.


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## MichaelE (Mar 7, 2018)

You would think that if a (any) company is producing an accurate model of a locomotive that any shell would fit on any chassis.

You would think.

Looks great. I don"t think I ever recall seeing that livery.


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## Andreash (Dec 30, 2018)

I was surprised that I didn’t need to modify the chassis length. The first time I put it on, it was a bear to take off. I had to run the dremel along the top 1/3 of the metal weight, and very gingerly on the inside of the athearn shell. Yes, it would have been easier to buy a ready made engine, but this paint scheme/engine is one I run very few times with a Amtrak passenger train (from a photo I saw on the internet). I do think I hated this paint scheme along time ago, but I must be softening up with old age...this paint scheme was started by SF and SP with a merger that wasn’t allowed....I believe after 400 locomotives were painted up...cheers


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## Andreash (Dec 30, 2018)

I ended up improving the athearn shell to the Bachmann chassis. I now can remove the shell without the wires going to the headlights or beacon. I found it a hassle to remove a shell when it’s tethered to the chassis. I mounted the lights on the chassis. Also cleaned up some of the wiring as well...I also improved the beacon mount on the athearn shell...


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