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Baldwin "DRS-6-6-1500" Locomotives

Last revised: June 1, 2023

By: Adam Burns

The DRS-6-6-1500 was the final road switcher to carry Baldwin's early and complicated designation system.  In 1950 it released its new Standard line, a fitting name since it did away with the confusing numbers, dashes, and letters. 

This last model was a six-axle locomotive, C-C version of the DRS-6-4-1500 built during the late 1940s and well suited for branch line operations (although few ultimately sold). 


The DRS-6-6-1500 found buyers among a scattering of railroads and private companies but in the end could not reach the century mark in sales. 

Today, there are at least two examples known preserved; McCloud River Railroad #29 (preserved as Magma Arizona #10) at the Arizona Railway Museum and Southern Pacific #5208 preserved in its original colors and number at the California Stat Railroad Museum in Sacramento.


Erie Lackawanna DRS-6-6-1500 #1153 is seen here in Hornell, New York during the summer of 1971. This unit began its career as Erie #1153 in 1950.

The DRS-6-6-1500 began production in 1948 offering a high, continuous tractive effort of 64,200 pounds thanks to its six powered axles. 

This was a considerable selling point as the locomotive not only provided the highest such rating for any road switcher Baldwin offered up to that time but also any model then in production. 

Nothing then offered by Alco or EMD came close to matching such tractive ability.  During the late 1940s the only manufacturer to have even manufactured a C-C road switcher was Alco's RSD1. 

However, the RSD1 was primarily a specialized model built only for the U.S. Army during World War II and had ended production in 1946.

The DRS-6-6-1500 could produce 1,500 horsepower using Baldwin's supercharged 608SC prime mover, the same as the earlier DRS-6-4-1500 and DRS-4-4-1500.


While the DRS-6-6-1500 did not sell particularly well several Class I railroads around the country purchased at least a few units such as:

  • Bessemer & Lake Erie

  • Duluth South Shore & Atlantic

  • Union Pacific

  • Southern Pacific

  • Erie

  • Chicago & North Western

  • McCloud River Railroad

  • Northern Pacific

  • Union Railroad

  • Minneapolis Northfield & Southern

  • Tennessee Coal & Iron

  • Chesapeake & Ohio

Additionally, private companies like Kaiser Steel and Tennessee Coal & Iron Railroad also acquired a few examples. 

By the time production had ended in 1950 just 83 units had been sold, which included one B-unit that the Southern Pacific had requested, #5227. 

Buyers of the model found the locomotive useful despite its troublesome prime mover.  The curious lack of dynamic braking also likely hurt sales, a feature then standard on Electro-Motive and Alco products.

The Union Railroad of Pennsylvania acquired a small fleet of DRS-6-6-1500's and later re-engined them with EMD 567 prime movers (giving them the nickname as "Buffalos"). Two are seen here behind an NW2 near Hall on July 11, 1974. Doug Kroll photo.

The DRS-6-6-1500 saw only a two year run as Baldwin wrapped up production on the unit in September of 1950.

It was soon after replaced by the AS616, which featured an upgraded prime mover and used the company's more straightforward classification system. 

Data Sheet and Specifications

Entered Production2/17/1948 (Chicago & North Western #1501)
Years Produced2/17/1948 - 9/28/1950
Baldwin ClassDRS-6-6-1500/1 SC
Engine608SC, 6-Cylinder In-Line, Supercharged
Engine BuilderDe La Vergne
Carbody StylingBaldwin
Length (Between Coupler Pulling Faces)58'
Weight325,000 Lbs
Height (Top Of Rail To Top Of Cab)14'
Width10' 2"
Truck TypeGSC Rigid Bolster-Inside Sideframe Equalizers
Truck Wheelbase13'
Wheel Size42"
Traction Motors370F/G (6), Westinghouse
Traction Generator471A, Westinghouse
Auxiliary GeneratorYG42A, Westinghouse
Gear Ratio15:63
Tractive Effort Rating64,200 Lbs at 6.6 MPH
Top Speed65 MPH

Production Roster

Total Built = 83

Owner Road Number Baldwin Serial Number Construction Number Completion Date
Chicago & North Western15001734752/18/1948
Chicago & North Western15012734762/17/1948
Chicago & North Western15023734772/21/1948
Tennessee, Coal, Iron & Railroad15004737465/22/1948
Tennessee, Coal, Iron & Railroad15015737476/4/1948
Kaiser Steel1010A6737498/16/1949
Northern Pacific1777738388/12/1948
McCloud River Railroad288736532/16/1949
Bessemer & Lake Erie4019739882/16/1949
Bessemer & Lake Erie40210739891/27/1949
Union Railroad60811742152/2/1949
Union Railroad60912742162/4/1949
Union Railroad61013742172/3/1949
Union Railroad61114742182/7/1949
Union Railroad61215742192/6/1949
Union Railroad61316742202/12/1949
Union Railroad61417742212/14/1949
Southern Pacific520318742573/20/1949
Southern Pacific520419742584/15/1949
Southern Pacific520520742594/15/1949
Southern Pacific520621742605/10/1949
Southern Pacific520722742615/14/1949
Southern Pacific520823742625/14/1949
Southern Pacific520924742636/4/1949
Southern Pacific521025742646/10/1949
Southern Pacific521126742656/16/1949
Southern Pacific521227742666/20/1949
Texas & New Orleans (SP)18728742673/28/1949
Texas & New Orleans (SP)18829742684/9/1949
Kaiser Steel Corporation1010-B30744518/17/1949
Chicago & North Western150531744528/6/1949
Chicago & North Western150632744538/6/1949
Chicago & North Western150733742798/9/1949
Chicago & North Western150834742808/9/1949
Chicago & North Western150935742818/12/1949
Texas & New Orleans (SP)189367466712/2/1949
Texas & New Orleans (SP)190377467712/7/1949
Southern Pacific5213387467812/21/1949
Southern Pacific5214397467912/23/1949
Southern Pacific5215407468012/30/1949
Southern Pacific5216417468112/30/1949
Southern Pacific521742746821/6/1950
Southern Pacific521843746831/20/1950
Southern Pacific521944746841/20/1950
Southern Pacific522045746851/23/1950
Southern Pacific522146746861/24/1950
Southern Pacific522247746871/25/1950
Southern Pacific522348746881/27/1950
Southern Pacific522449746891/27/1950
Southern Pacific522550746901/27/1950
Southern Pacific522651746911/31/1950
Southern Pacific522752746921/31/1950
Duluth, South Shore & Atlantic (Soo Line)200537469311/7/1949
Duluth, South Shore & Atlantic (Soo Line)201547469411/11/1949
Duluth, South Shore & Atlantic (Soo Line)202557469511/15/1949
Union Railroad620567469610/4/1949
Union Railroad621577469710/12/1949
Union Railroad622587469810/12/1949
Union Railroad623597469910/2/1949
Union Railroad624607470010/13/1949
Chesapeake & Ohio5530617470111/7/1949
Chesapeake & Ohio5531627470211/11/1949
Chesapeake & Ohio5532637470311/12/1949
Erie Railroad115064747144/28/1950
Bessemer & Lake Erie40365747155/29/1950
Baldwin Locomotive Works1500*66747164/1950
Erie Railroad115167747176/28/1950
Erie Railroad115268747186/28/1950
Erie Railroad115369747199/19/1950
Minneapolis, Northfield & Southern1570747583/3/1950
Erie Railroad115471747799/19/1950
Erie Railroad115572747809/21/1950
Erie Railroad115673747819/21/1950
Erie Railroad115774747829/21/1950
Erie Railroad115875747839/25/1950
Erie Railroad115976749309/25/1950
Erie Railroad116077749319/28/1950
Erie Railroad116178749329/28/1950
Bessemer & Lake Erie40479749337/6/1950
Bessemer & Lake Erie40580749347/10/1950
Bessemer & Lake Erie40681749357/11/1950
Bessemer & Lake Erie40782749367/12/1950
McCloud River Railroad2983748127/28/1950

Southern Pacific units featured upgraded components including 471B main generator, YG42B auxiliary exciter generator, and 370DL or 370GL traction motors.

* This unit became Duluth, South Shore & Atlantic (Soo Line) #203 on August 23, 1950.


  • 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.

A Baldwin Locomotive Works builder's photo of new Chicago & North Western DRS-6-6-1500 #1500 circa 1948.

The new series sold much better for the builder seeing several hundred examples outshopped amongst the three primary models (AS16, AS416, and the AS616). 

To decipher the meaning of the DRS-6-6-1500's letters and numbers the DRS referred to Diesel Road Switcher unit; the first number, 6, designated its six powered axles; the second 6 meant that it featured six traction motors; and 1500 stood for the horsepower rating.

Once the system is presented it is fairly easy to understand but anyone looking at it for the first time would likely be quite confused at what everything stood for.  

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