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Baldwin's "S-8": Its First Switcher In The 'Standard Line'

Last revised: May 31, 2023

By: Adam Burns

The S-8 was Baldwin's first diesel switcher as part of its latest Standard Line.  It specifically replaced the earlier "DS" line and the DS-4-4-750.  The latest model offered a slight increase in horsepower (50 hp).

The switcher itself was not considerably different from its earlier counterpart although it did feature an upgraded prime mover of the same version used in the DS-4-4-750.  Baldwin simply dropped the "Normally Aspirated" (NA) title.

Perhaps the most noticeable change was merely the S-8's designation, as the Baldwin looked to simplify its earlier classification system of complicated numbers, dashes, and letters. Overall, the S-8 was not particularly successful although its successor, the S-12, did see decent sales.

One railroad which never wavered on Baldwin was the Pennsylvania; the PRR was a loyal buyer of steam locomotives practically from its inception and continued supporting the company until the end.  It acquired a small roster of six S-8's.


Oliver Iron Mining Company S-8's #1201-A and #1200-B push a string of side dump cars up the slope and toward the mine at Virginia, Minnesota on August 18, 1970. Jim Jeffery photo. American-Rails.com collection.


The S-8 switcher line debuted in 1951 featuring Baldwin's updated 606 prime mover. The locomotive could produce 800 horsepower using a B-B truck arrangement (two axles per truck).

Overall Baldwin designed the S-8 as a standard yard switcher although sales never truly materialized. Railroads still preferred more powerful models and the company had a difficult time finding orders for any of its lightly powered designs like the VO660, DS-4-4-750, and the S-8.

Of course, this was not unique to Baldwin. The American Locomotive Company, for instance, also saw only lukewarm sales for its small switchers such as the S-1, S-3, and S-6.

At 48 feet in length the S-8 was nearly identical to the DS-4-4-750 using the same basic frame and design (end cab and long trailing hood).

The one operational standout, aside from its extra 50 horsepower was the additional tractive effort; 59,550 pounds starting and 34,000 pounds continuous.

This gave the locomotive the ability to pull a string of loaded cars with relative ease while being agile and light enough (just 100 tons) to be used almost anywhere. Because of this, several industries found the S-8 to their liking.


By the time production had ended Baldwin was able to sell 65 total units (56 A units and 9 B units/calves) to a wide range of buyers.

While Class I railroads purchased the S-8, such as the Pennsylvania and Rock Island, many buyers turned out to be industrial operations like mining and steel companies.

These included:

  • American Rolling Mill Company

  • Oliver Iron Mining Company

  • Sharon Steel Corporation

  • Sloss-Sheffield Steel

  • US Pipe and Foundry

  • US Steel

  • Weyerhaeuser Company

  • Youngstown Sheet and Tube

Interestingly, before the Cuban trade embargo was implemented Baldwin also sold two S-8s to United Railways of Havana.  

As John Kirkland notes in his book, "The Diesel Builder: Volume Two," the S-8 was essentially the DS-4-4-750 with an additional 50 horsepower and dropping the prime mover's designation from 606NA to simply 606.

Data Sheet and Specifications

Entered Production3/22/1951 (Pennsylvania #8994)
Years Produced3/22/1951-7/28/1953
Baldwin ClassS-8
Engine606, 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

Production Roster

Total Built = 63

(53 "A" Units and 10 "B" units)

Owner Road Number Baldwin Serial Number Construction Number Completion Date
Oliver Iron Mining Company1200A7752437/29/1951
Oliver Iron Mining Company1201A8752447/31/1951
Oliver Iron Mining Company1202A9752458/27/1951
Oliver Iron Mining Company1203A10752468/27/1951
Oliver Iron Mining Company1200B11742477/29/1951
Oliver Iron Mining Company1201B12742487/31/1951
Oliver Iron Mining Company1202B13742498/27/1951
Oliver Iron Mining Company120314742508/27/1951
Pennsylvania-Reading Seashore Lines600615752535/16/1951
New Orleans Public Belt5016752515/10/1951
New Orleans Public Belt5117752525/16/1951
Weyerhaeuser Company10318752546/30/1951
Weyerhaeuser Company10519752556/30/1951
Sharon Steel Corporation320754213/10/1952
Sharon Steel Corporation421754227/31/1952
Sharon Steel Corporation522754238/2/1952
Sharon Steel Corporation623754248/21/1952
Sharon Steel Corporation724754252/13/1953
Sharon Steel Corporation825754262/16/1952
Sharon Steel Corporation926754278/28/1953
Sharon Steel Corporation1027754288/28/1953
LaSalle & Bureau County8287542910/23/1951
Youngstown Sheet & Tube703297543011/30/1951
Medford Corporation830754813/21/1952
Oliver Iron Mining Company1204A317548810/31/1951
Oliver Iron Mining Company1205A327548911/29/1951
Oliver Iron Mining Company1206A337549011/29/1951
Oliver Iron Mining Company1204B347549110/31/1951
Oliver Iron Mining Company1205B357549211/29/1951
Oliver Iron Mining Company1206B367549311/29/1951
Youngstown Sheet & Tube80037754943/17/1952
Youngstown Sheet & Tube80138754953/15/1952
Youngstown Sheet & Tube80239754963/18/1952
Youngstown Sheet & Tube80340754973/20/1952
Sloss-Sheffield Steel33417552012/18/1951
Sloss-Sheffield Steel34427552112/18/1951
Sloss-Sheffield Steel3543755223/26/1952
Sloss-Sheffield Steel3644755233/26/1952
American Rolling Mill Company1151457552712/12/1951
Chicago, Rock Island & Pacific80246756839/9/1952
Chicago, Rock Island & Pacific80347756849/9/1952
Chicago, Rock Island & Pacific80448756859/10/1952
Chicago, Rock Island & Pacific80549756869/10/1952
Chicago, Rock Island & Pacific80650756879/12/1952
Oliver Iron Mining Company1214A51756926/5/1952
Oliver Iron Mining Company1215A52756936/6/1952
American Rolling Mill Company1152537498810/30/1952
Youngstown Sheet & Tube80454751632/10/1953
Oliver Iron Mining Company1214B55756966/5/1952
Oliver Iron Mining Company1215B56756976/16/1952
Youngstown Sheet & Tube80557753322/10/1953
Oliver Iron Mining Company1216A58758347/1952
Escanaba & Lake Superior10259757008/21/1952
United Railways Of Havana800160757196/19/1952
United Railways Of Havana800261757206/19/1952
Oliver Iron Mining Company1216B63758367/1952
U.S. Steel1365753997/28/1953


  • Foster, Gerald. A Field Guide To Trains. New York: Houghton Mifflin, 1996.
  • Kirkland, John F. Diesel Builders, The:  Volume Three, Baldwin Locomotive Works. Pasadena: Interurban Press, 1994.
  • Pinkepank, Jerry A. Diesel Spotter's Guide.  Milwaukee: Kalmbach Publishing Company, 1967.
  • Solomon, Brian.  Baldwin Locomotives.  Minneapolis:  Voyageur Press, 2009.

One particular note of interest about the S-8s were the nine cow-calf sets purchased by Oliver Mining. Oliver was the only buyer to request such a setup (it also ordered other cow-calf sets from Baldwin).

The units were numbered 1200A-1206A, 1214A-1215A/1200B-1206B, 1214B-1215B and the mining company had on order a tenth set but later canceled this after it was already completed. Baldwin then retrofitted the B unit with a cab and resold it as a standard S-8.  


Today, at least two S-8s are preserved:

  • U.S. Pipe & Foundry #37 at the Heart of Dixie Railroad Museum
  • Medford Corporation #8 at the Southern Oregon Chapter, NRHS


Wes Barris's SteamLocomotive.com is simply the best web resource on the study of steam locomotives. 

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

It is quite staggering and a must visit!