Can someone please tell me what this rebuild is?

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MWLX is the reporting mark for Mid West Locomotive Works. Given that it has standard AAR-type trucks, it may well have been rebuilt from an Alco, but Mid-West, like the other locomotive rebuilders, tend to apply their own model designations to the locomotives they rebuild. This one has obviously been rebuilt from the frame up; it has a completely different hood and cab to an S-4. The exhaust stack is at the other end of the hood to an S-4, so it has probably been refitted with a new prime mover as well. What I'm asking is, does anyone know the Mid-West model designation for this locomotive, and hopefully someone can tell me what prime mover it's been refitted with, as well.

Bill Anderson

Well-Known Member
I looked up the Midwest Locomotive Works roster on The Diesel Shop and Railroad Picture Archives. Neither roster was current and MWLX 240 did not appear in either. I did note that all of the MLX rebuilds are EMD products, including some SW9's. Neither roster gave MWLX model designations.

Early EMD switchers used AAR type trucks with the drop equalizers. I will guess that MWLX 240 started life as an SW9 or similar small EMD switcher, but who knows how much of the original unit remains after rebuilding, including the prime mover.
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Yeah, I think I might have been barking up the wrong tree. (Sorry, bnsf971!) I think I have incorrectly assumed that Mid West were the rebuilder. The 'Green Plains' misled me; it probably isn't a Tier 4 repower at all, because Don Ross's page shows some old photos of this unit in the same configuration. I wonder where it is now? is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to