Baldwin "DS-4-4-750" Locomotives

The Baldwin DS-4-4-750 was a lightly powered switcher locomotive built during just a few year stretch in the late 1940s and early 1950s. More powerful than its counterpart the DS-4-4-660 but less powerful than the DS-4-4-1000 the "specialized" model saw only lukewarm interest and was the company's worst selling design.

The Baldwin Locomotive Works had a pessimistic view towards diesel locomotives as an inferior motive power type in comparison to steam, and as such mostly ignored it for main line service.  This, along with the fact that the company believed customizing orders to fit railroads' specific needs was more important than offering standard designs would ultimately cost it as a manufacturer.  

Baldwin would exit locomotive production during the 1950s. Today, at least two DS-4-4-750's are known to be preserved, Texas Mexican #510 at the Gulf Coast Railroad Museum and Warner Sand & Gravel #14 owned by the Reading Company Technical & Historical Society.

Santa Fe DS-4-4-750 #631 (built as #533 in July, 1949) switches train #1, the westbound "San Francisco Chief," at Amarillo, Texas during the mid-1960's. Note the train is powered by Alco PA's, which were nearing retirement by this date. Roger Puta photo.

The Baldwin DS-4-4-750 began production in the summer of 1949 using the builder's 606NA model prime mover. Producing 750 horsepower, the DS-4-4-750 was a mid-grade switcher as Baldwin also produced a 660 horsepower and 1,000 horsepower model.

Using a B-B truck arrangement (i.e., two axles per truck) the model found a diversity of buyers from Class I railroads like the Pennsylvania, Erie, and Santa Fe to industrial companies like American Cynamid, Youngstown Sheet & Tube, and American Steel & Wire.

As with the American Locomotive Company (Alco), Baldwin at the time still held a loyal following by some railroads that had worked with it for years during the reign of steam.

Because of this it probably explains why roads like the Pennsylvania (an avid buyer of Baldwin products) and Erie purchased the DS-4-4-750. The PRR, for instance, purchased examples of nearly every Baldwin diesel it produced.

Ultimately, however, few DS-4-4-750s actually purchased as only 53 were ever built through February, 1951 (three of which being the demonstrators #301, #750, and #751 that were eventually sold to Weyerhaeuser Timber).

The locomotive was essentially a DS-4-4660/VO660 with slightly more horsepower. For instance, along with the above mentioned characteristics it was also 46 feet in length, offered the same tractive effort (49,625 pounds starting/34,000 pounds continuous), and featured the same general exterior carbody features (end cab and trailing long hood).

Additionally, the model did not offer either dynamic braking or turbocharging (which to some extent could have also been a negative sales point as Alco, for instance, did offer both features in most of its switchers).

A Baldwin company photo (1950) of a new Pennsylvania Railroad DS-4-4-750, which has yet to receive its number. The PRR acquired 24 examples, #5595-5618.

After less than two years in production, Baldwin removed the DS-4-4-750 from its catalog, replacing it with the S-8 (the offered just slightly more horsepower) and the more powerful S-12. The DS-4-4-750 also ended the company's use of its confusing classification system.

In 1950, after it released upgraded prime movers (the model 606 and 608) it likewise used a simpler system of model type and horsepower (for instance, the S-12 meant Switcher, 1,200 horsepower). Finally, for more information about the DS-4-4-750s please refer to the chart below.  

Baldwin DS-4-4-750 Data Sheet

Entered Production7/15/1949 (Santa Fe #525)
Years Produced7/15/1946-2/23/1951
Baldwin ClassDS-4-4-750
Engine606NA, 6-Cylinder In-Line
Engine BuilderDe La Vergne
Carbody StylingBaldwin
Length (Between Coupler Pulling Faces)48'
Weight200,000 Lbs
Height (Top Of Rail To Top Of Cab)14'
Truck TypeGSC Rigid Bolster, Drop-Side Equalizer
Truck Wheelbase8'
Wheel Size40"
Traction Motors362D (4), Westinghouse
Traction Generator480F, Westinghouse
Auxiliary GeneratorYG42A, Westinghouse
Gear Ratio16:76
Tractive Effort Rating33,600 Lbs at 8.3 MPH.
Top Speed45 MPH

Baldwin DS-4-4-750 Production Roster

Owner Road Number Baldwin Serial Number Construction Number Completion Date
Atchison, Topeka & Santa Fe5251743947/15/1949
Atchison, Topeka & Santa Fe5262743957/27/1949
Atchison, Topeka & Santa Fe5273743967/14/1949
Atchison, Topeka & Santa Fe5284743977/14/1949
Atchison, Topeka & Santa Fe5295743987/16/1949
Atchison, Topeka & Santa Fe5306743997/15/1949
Atchison, Topeka & Santa Fe5317744007/23/1949
Atchison, Topeka & Santa Fe5328744017/23/1949
Atchison, Topeka & Santa Fe5339744027/19/1949
Youngstown Sheet & Tube60810744058/8/1949
Youngstown Sheet & Tube60911744068/8/1949
Youngstown Sheet & Tube61012744078/8/1949
California Western5113744088/19/1949
California Western5214744098/19/1949
Erie Railroad38615744308/5/1949
Erie Railroad38716744318/5/1949
Erie Railroad38817744328/5/1949
Erie Railroad38918744338/5/1949
Texas-Mexican Railway50919745947/16/1949
Texas-Mexican Railway51020745957/18/1949
American Steel & Wire2021746748/16/1949
American Cyanamid Company1446747843/24/1950
Warner Company1447747854/4/1950
Baldwin750 (Became Weyerhaeuser Timber Company #101)49748146/1950
Baldwin751 (Became Weyerhaeuser Timber Company #102)50748156/1950
Weyerhaeuser Timber Company1014974814Acquired 10/28/1950
Weyerhaeuser Timber Company1025074815Acquired 11/15/1950
Youngstown Sheet & Tube70051736572/21/1950
Youngstown Sheet & Tube70152736582/22/1950
Youngstown Sheet & Tube70253736592/23/1950

* Originally Baldwin's plant switcher, #300.  It became Weyerhaeuser Timber #301 on January 29, 1956.


  • Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.

  • Kirkland, John F. Diesel Builders, The:  Volume Two, American Locomotive Company And Montreal Locomotive Works. Glendale: Interurban Press, 1989.

  • Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.

  • Solomon, Brian.  Baldwin Locomotives.  Minneapolis:  Voyageur Press, 2009.

Santa Fe DS-4-4-750 #627, built as #527 in July, 1949.

For more information on Baldwin locomotives the book by the same name, a Brian Solomon title, provides an in-depth history of the company from its earliest days beginning in the 1930s to its final years constructing diesels during the mid-20th century.  

It 160 pages in length and, as with every Solomon book, offers a rich collection of large, sharp photos to enjoy.  Another title of interest is Vintage Diesel Locomotives by noted author and historian Mike Schafer.

This one has been out for several years now and is a paperback title but highlights several classic models from the major builders of the era such as Electro-Motive, Baldwin, and the American Locomotive Company.

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Header Photo: Drew Jacksich

Wes Barris's is simply the best web resource in the study of steam locomotives. 

The amount of information found there is quite staggering; historical backgrounds of wheel arrangements, types used by virtually every railroad, preserved and operational examples, and even those used in other countries (North America and beyond). 

It is difficult to truly articulate just how much material can be found at this website.  It is a must visit!

Researching Rights-Of-Way

A popular pastime for many is studying and/or exploring abandoned rights-of-way. 

Today, there are tens of thousands of miles scattered throughout the country.  Many were pulled up in the 1970's and 1980's although others were removed long before that. 

If you are researching active or abandoned corridors you might want to check out the United States Geological Survey's (USGS) Historical Topographic Map Explorer

It is an excellent resource with thousands of historic maps on file throughout the country.  Just type in a town or city and click on the timeline of maps at the bottom of the page!