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Bruce Butler

Nice to see that UP knows how, and is willing to update older locomotives for continued service. Seems such a waste to just scrap them. I hope that the 99** number doesn't mean that it is a short-timer.

I found this description on

This is an SD60M that has gone through the EMD SD32ECO program, and is designated SD59M-2 by EMD, and SD59MX by UP.

And this from:

In the ECO repower line:
UP SD59MX 9907 which had been repainted and renumbered by UP before being returned to London. Some of the London-rebuilt UP SD60M's with the ECO package (called SD32ECO - EMD Marketing Name, SD59M-2 - EMD Official Designation and SD59MX - UP Designation) are now in service on UP (details: Bill Miler and photo credit to Don Kalkman).

This is from LocoNotes Yahoo site:
Again, SD32ECO was a marketing name. EMD officially calls them SD59M-2s.
V12 710 ECO engines turbocharged.

Interestingly, a visit to the "official" EMD web site at makes no mention of the ECO program; at least none that I could find.
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Bruce Butler


Thanks for finding and providing this link. It has lots of good information.

One observation, though. On page 2 where they give the "710ECO Repower Technical Specification", for the model SD32ECO they state that the engine model is a "12–710G3B–T2" but the picture shows a 16 cylinder engine!

I sent the following to the EMD web site under their "contact us" page:
Your link at:

is very informative about your ECO models. However, on page 2 for the model SD32ECO it states that the engine model is a "12–710G3B–T2" but the picture shows a 16 cylinder engine!

You should replace this picture with one of a 12-cyl engine.
It says "Your inquiry has been received successfully.". Now, lets see if they do anything about it.
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