• Exactly when did EMC become EMD?

  • Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.
Discussion of Electro-Motive locomotive products and technology, past and present. Official web site can be found here: http://www.emdiesels.com/.

Moderator: GOLDEN-ARM

  by depotsquare
From reading through some of the discussion threads in this forum it appears that a number of you are quite knowledgeable regarding General Motors-built Diesel locomotives, so maybe someone can answer several questions I have regarding them.

When looking at various sources on the Internet, I find conflicting opinions as to the date when Electro-Motive Corporation ceased as a legal corporate identity and the Electro-Motive Division of General Motors began. One on-line reference involving Harold Lee Hamilton states that EMC became EMD in 1942; in one of this forum’s threads the date of January 1, 1941 is supplied, while Electro-Motive Diesel’s own web pages seemingly places the changeover circa 1934—it isn’t clear.

Adding to my confusion are the builder credits and their associated dates given to GM-produced Diesels. From one book covering the New York Central comes the following:

Indiana Harbor Belt #8733, Model NW2, EMC #6380, September 1948
Indiana Harbor Belt #8734, Model NW2, EMD #6416, September 1948

Indiana Harbor Belt #8855, Model SW7, EMC #9455, February 1950
Indiana Harbor Belt #8856, Model SW7, EMD #9121, February 1950

As one can plainly see, each of the IHB references implies a solid, yet separate (as well as post-World War II), period for the EMC/EMD transition. I know of one instance where I saw an official GM Electro-Motive Corporation #2300 E7 operating manual issued for the New York Central that contained the publication year of 1945, so this, too, points toward an EMC/EMD identity change after WWII.

There also seems to be a further paradox in having the EMC SW7 construction number higher than the EMD number. This last is also found when comparing the IHB NW2 units with the below:

New York Central #585, Model SW1 (light), EMD #6391, April 1949

So this begs the following questions:

1) Exactly when did General Motors reincorporate or reorganize Electro-Motive Corporation into Electro-Motive Division?

2) Since an early 1940s date for the corporate change of EMC into EMD will conflict with the IHB information supplied, can someone explain why EMC is credited with building (at least some) Diesel locomotives in the late 1940s/early 1950s? Was there an extended subsidiary relationship that required showing both names as the builder during this WWII period?

3) Why are there lower EMD construction numbers versus EMC? Were EMC/EMD construction numbers assigned based on when the railroads placed orders or when the locomotives rolled off the assembly line?

4) Is there a comprehensive Diesel roster available (paper hard-copy, on-line, CD) that reliably identifies EMC/EMD-built locomotives while providing each unit’s corresponding date of construction?

5) Would On Time: The History of Electro-Motive Division of General Motors Corporation by Franklin Reck (published 1948) or other historical titles shed any light?

Thanks for any help that can be provided.

John Hudson
Depot Square Publishing

  by Nelson Bay
From Franklin Reck's 1948 "On Time";

Electro-Motive Engineering Corporation was incorporated at Cleveland, Ohio on August 31, 1922. Late in 1923 it changed its name to Electro-Motive Company. On June 20, 1930 General Motors Corporation bought Winton Engine Company and on December 31st purchased Electro-Motive Company.

Hope this is helpful.

  by Phil Hom
My timeline record shows EMC became part of the General Motors family on 31 Dec 1930 (six months after GM purchased Winton (20Jun30).

GM changed Electro Motive's standing from a company to a division on 01Jan1941.

The builder's plate remained the cast bronze version listing as EMC until the oval (hotdog) version came out in late 40's (during F3 & E7 production) listing as EMD.

Some of the EMC/EMD data may have been recorded in error. Some books have factual errors in the roster which gets carried over and over.