1. Home
  2.  ›
  3. Diesel Locomotives
  4.  ›
  5. T-6

Alco "T6" Switcher Locomotives: Specs, Roster, Data Sheet

Last revised: December 21, 2024

By: Adam Burns

The T6 can be classified within the S series because the design is basically an S6 with an additional 100 horsepower and intended for use in slow, drag service (the "T" designation simply stood for Transfer switcher).

This type of locomotive dated back to the 1940s with the Baldwin Locomotive Works' DT-6-6-2000 and later RT624 models believing that there was a market for this type of switcher moving cuts of cars or freight over short distances (such as terminal operations or between yards).

However, the idea never really caught on as railroads saw little use for a such a specialized design believing (quite correctly) that standard switchers or small road switchers (like early Geeps and RS models) could perform that task just as well. 

From a broader perspective, Alco did have more success than Baldwin's models, which were simply too long, bulky and inefficient to be particularly useful. 

Today, at least four Alco T6s are preserved; Norfolk & Western #41 is the most notable, which is owned by the Roanoke Chapter of the National Railroad Historical Society.

Photos

91232735762357823894692468947.jpgChesapeake Western T6s #11 and #10 are seen here at work in Elkton, Virginia on August 27, 1979. Warren Calloway photo.

Overview

The American Locomotive Company (Alco), despite knowing of Baldwin's unsuccessful earlier models went ahead and released the T6 in late 1958 still believing that there would be a market for such a locomotive.

Even the Electro-Motive Division, the industry leader since main line diesels first hit the market in the late 1930s, understood that there was not a significant market for transfer switchers.

The Alco T6 debuted in March, 1958 and as can probably be guessed was most successful with industries and in mining applications including Brewster Phospahtes, Kaiser Steel, Portland Terminal Railroad, Newburgh & South Shore, and the Monongahela Connecting Railroad.

However, a few Class Is also found an interest in the model including the Norfolk & Western and Pennsylvania railroads purchased the T6. Additionally, Altos Hornos de Mexico, S.A. also picked up two units.

The T6 (which was designated by the company as its DL440) was almost identical to the S6 save for its notched number boards, a later Alco hallmark (particularly for the Century line) that no other model within the S series featured.

The T6 also differed from previous models in that it was a foot longer at 46 feet, 5 inches and also featured a slightly taller hood. Aside from these differences the transfer design was about the same internally; it featured a B-B truck setup using General Electric traction motors and generators as well as Westinghouse components.

Interestingly, the locomotive's tractive was a bit less than the S6; 60,000 pounds starting and 46,000 pounds continuous.

Reception

For the 57 examples of Alco T6s built they were apparently well liked, particularly by the Norfolk & Western, which purchased 40 of them. The N&W found them especially useful along the extreme eastern region of their system near the ports of Norfolk, Virginia.

There they were used for years shuffling empty and loaded coal hoppers, and other relevant freight, around the docks located there. Some of the units even continued to operate into the early Norfolk Southern years although all were retired soon afterwards. 

Data Sheet and Specifications

Entered Production3/14/1958 (Pennsylvania #8424)
Years Produced3/14/1955-1/10/1969
Model SpecificationDL440
Engine251B, 6-Cylinder In-Line
Horsepower1000
RPM1000
Carbody StylingAlco
Length (Between Coupler Pulling Faces)45' 5.75"
Width10'
Height Above Rail Head14' 6"
Weight230,000 Lbs. or 248,000 Lbs.
TrucksB-B
Truck TypeGRS Rigid Bolster, Drop-Side Equalizer
Truck Wheelbase8'
Wheel Size40"
Traction MotorsGE 752 (4)
Traction GeneratorGT854
Gear Ratio74:18
Tractive Effort Rating46,000 Lbs. at 8 MPH.
Top Speed60 MPH

Production Roster

Total Built = 57

Owner Road Number(s) Serial Number(s) Completion Date
American Cyanamid 16, 17 3454-01, -02 6/1966, 7/1966
Kaiser Steel 1022, 1023 83392, 83393 12/1959
Monongahela Connecting 400 6004-01 7/1968
Newburg & South Shore 1016, 1017 6017-01, -02 1/1969
Norfolk & Western (Chesapeake Western) 10, 11 82309, 82310 1/1959
Norfolk & Western 12 - 21 82313-82322 2/1959-3/1959
Norfolk & Western 22 - 49 83364-83391 4/1959-10/1959
Pennsylvania 8424 - 8429 82857-82862 3/1958
Portland Terminal (Oregon) 46, 47 3489-01, -02 2/1968
Altos Hornos de México (AHMSA) 126, 127 3391-01, -02 12/1964
26293582936723986897384948728789.jpgPenn Central T6 #9844 (ex-Pennsylvania #8424) is seen here in Old Bridge, New Jersey on the New York & Long Branch, circa 1969. Fred Byerly photo. American-Rails.com collection.

Preservation

Interestingly, despite the few T6s ever built there are actually numerous examples still operational aside from the one N&W unit preserved. 

These units include Middletown & Hummelstown #1016 is an original Newburg & South Shore unit; Arkansas & Missouri operates six, #12, #14, #16, and #18 are original N&W units while #15 and #17 are of Pennsylvania Railroad lineage; and International Terminals #9624. 

From a historical standpoint, the T6 was the final locomotive ever outshopped by the American Locomotive Company when Newburgh & South Shore Railroad #1016 and #1017 rolled out of the Schenectady plant in January, 1969. 

Recent Articles

  1. FRA Awards $1.24 Billion for Grade-Crossing Work in 37 States

    Nov 01, 26 12:48 PM

    apollo-road-eaganmt-dk.jpg
    The Federal Railroad Administration on October 30, 2026, awarded $1.24 billion for 91 grade-crossing projects in 37 states under the Railroad Crossing Elimination program.

    Read More

  2. PATH Director Clarelle DeGraffe Will Retire at the End of 2026

    Nov 01, 26 12:43 PM

    Clarelle DeGraffe will retire at the end of 2026 after 37 years with the Port Authority of New York and New Jersey. James Sincaglia will succeed her as PATH director.

    Read More

  3. Lehigh Gorge Scenic Railway Suspends Trains After a Rockslide

    Nov 01, 26 12:30 PM

    lgcr-gp39rn-dk.jpg
    The Lehigh Gorge Scenic Railway has suspended all trains indefinitely after a rockslide near Jim Thorpe, Pennsylvania, on October 31, 2026. Tickets through November 15 will be refunded.

    Read More

  4. Georgia Marks the Opening of the Gainesville Inland Port

    Nov 01, 26 12:06 PM

    gainesvilleport-ribboncutting.jpg
    Norfolk Southern and Georgia Ports marked the Gainesville Inland Port on October 29, 2026. The terminal opened May 4 and can handle 200,000 containers a year at full build-out.

    Read More

  5. BLET Members Ratify Five-Year Deal on the Dakota, Minnesota & Eastern

    Nov 01, 26 11:48 AM

    cpkc-media-blet.jpg
    Brotherhood of Locomotive Engineers and Trainmen members have ratified a five-year agreement with CPKC covering Dakota, Minnesota and Eastern lines. Engineers' hourly pay rises 41.42 percent over the…

    Read More

  6. Canada Lists Roberts Bank Terminal 2 as a Project of National Interest

    Nov 01, 26 11:03 AM

    On October 30, 2026, Canada listed the Roberts Bank Terminal 2 container project at the Port of Vancouver as a project of national interest. The listing includes a widened causeway for rail.

    Read More

  7. Amtrak Finishes the First Street Tunnel Work South of Union Station

    Nov 01, 26 09:59 AM

    amtrak-tunnel-cmplt.jpg
    Amtrak on October 26, 2026 finished nine days of work at A Interlocking in the First Street Tunnel south of Washington Union Station. Trains south of the station are back.

    Read More

  8. CPKC Asks the STB to End the Union Pacific-Norfolk Southern Review

    Nov 01, 26 12:23 AM

    cpkc-4805.jpg
    CPKC on October 30, 2026 asked the Surface Transportation Board to end its review of the Union Pacific-Norfolk Southern merger, citing remarks by the Union Pacific chief executive.

    Read More

  9. U.S. Rail Traffic Rose 7.8 Percent in the Week Ending October 24

    Nov 01, 26 12:13 AM

    wnyp-franklin-fall-dk.jpg
    U.S. railroads moved 538,503 carloads and intermodal units in the week ending October 24, 2026, up 7.8 percent from a year earlier, the Association of American Railroads said.

    Read More

  10. Schneider Will Shift Its Eastern Intermodal Freight to NS

    Nov 01, 26 12:06 AM

    ns-217-bluefield.jpg
    Schneider said October 29, 2026 that Norfolk Southern will be its primary eastern railroad. The move from CSX begins next month, with official implementation on January 1.

    Read More

  11. Union Pacific Dispatchers Will Vote on ATDA Representation

    Nov 01, 26 12:00 AM

    up-barstow-ll.jpg
    The National Mediation Board has authorized a representation election for Union Pacific train dispatchers. The American Train Dispatchers Association announced the decision on October 29, 2026.

    Read More

  12. Wabash Diesel Roster (All-Time)

    Oct 31, 26 12:35 AM

    28374236529735892362689389708.jpg
    Wabash diesel locomotives, each frame once, through the lease at 12:01 a.m. on October 16, 1964.

    Read More

  13. Wabash Steam Roster (Built Since 1900)

    Oct 31, 26 12:30 AM

    67o10293172461y242795086260970978.jpg
    Wabash steam locomotives built since 1900. Moguls, Mikados, Mountains, and the O-1 Northerns.

    Read More

  14. Wabash Railroad: Map, Rosters, History, Logo

    Oct 31, 26 12:28 AM

    91287365123512534162471587189569.jpg
    History of the Wabash Railroad, from the Northern Cross of 1838 to the Norfolk & Western lease at 12:01 a.m. on October 16, 1964. Follow the Flag. Steam and diesel rosters are separate pages.

    Read More

  15. Court Clears $257.7 Million in Notes for Brightline Florida

    Oct 31, 26 12:18 AM

    brightline-delray-dk.jpg
    A New Jersey bankruptcy court on October 29, 2026 authorized $257.7 million in notes for Brightline Trains Florida. The operating company is not one of the 17 debtor holding companies.

    Read More

  16. Brightline West Still Waiting on a $6 Billion Federal Loan

    Oct 31, 26 12:11 AM

    brightilne-west-media.jpg
    Brightline West said October 27, 2026 that it is still working through a $6 billion federal loan and still talks about opening in 2029. The Florida restructuring is a separate company.

    Read More

  17. BNSF Reopens the Gallup Subdivision After New Mexico Flooding

    Oct 31, 26 12:06 AM

    bnsf-reopen-gallup.jpg
    BNSF said October 28, 2026 that both Gallup Subdivision main tracks are back after flooding near Laguna, New Mexico. The El Paso Subdivision was still out of service.

    Read More

  18. CSX Says Interchange Is Moving Again After a Technology Outage

    Oct 31, 26 12:01 AM

    csx-rabbit-2021-rb.jpg
    CSX said October 29, 2026 that interchange with other Class I railroads is moving again after a technology outage that began October 27. Dispatching and positive train control stayed up.

    Read More

  19. Baldwin "Baby Face" Locomotives: Specs, Photos, Roster

    Oct 30, 26 11:01 PM

    nyc-dr441500-3401.jpg
    Baldwin's Babyface cab on the early road diesels: 50 short-cab units, 1946-1948, plus the related Centipede. Construction numbers, specs, and the sharknose that followed.

    Read More

  20. California High-Speed Rail Chief Resigns

    Oct 30, 26 08:36 PM

    san-joq-bridge.jpg
    Ian Choudri resigned October 28, 2026 as chief executive of the California High-Speed Rail Authority. The board named Joe Stephenshaw interim chief executive.

    Read More

  21. The 1910 Portal Bridge Is Handed Over for Demolition

    Oct 30, 26 04:03 PM

    portal-bridge-demo.jpg
    Amtrak handed the 1910 Portal Bridge over for demolition on October 29, 2026, during the final cutover to Portal North. Regular NJ Transit and Amtrak schedules are expected November 15.

    Read More

  22. Union Pacific-Norfolk Southern Merger Review Runs to 2027

    Oct 30, 26 03:59 PM

    up-7663-rb.jpg
    Union Pacific says the Surface Transportation Board's review of the Norfolk Southern merger gathers information through May 28, 2027. A closing still depends on board approval.

    Read More

  23. Amtrak Board Will Hear Restructuring Comments on November 10

    Oct 30, 26 03:41 PM

    amtrk-trn-371-rb.jpg
    Amtrak's board will hear public comments on its restructuring on November 10, 2026, from 2 to 3 p.m. Eastern. Written comments were due October 30. A proposal goes to the board in December.

    Read More

  24. Canadian Pacific Selkirk 5931 Restored in Calgary

    Oct 30, 26 01:36 PM

    cp-5931-palliser.jpg
    Heritage Park in Calgary unveiled a cosmetic restoration of Canadian Pacific 2-10-4 No. 5931 on October 27, 2026. One of two surviving Selkirks. It stays on display.

    Read More

  25. Gettysburg Railway to Host Steam for Lincoln

    Oct 30, 26 01:18 PM

    440-york-17-jw.jpg
    Northern Central Railway of York No. 17 will recreate Lincoln's arrival at Gettysburg on November 18, 2026, with public steam trips November 19-21.

    Read More

  26. NC&StL No. 576 to Steam for the Public in Nashville

    Oct 30, 26 01:00 PM

    ncstl-484-576-alco.jpg
    Nashville Steam will fire NC&StL 4-8-4 No. 576 for the public on November 7, 2026, 9 a.m. to 3 p.m., at 220 Willow Street. Admission is free.

    Read More

  27. Pennsylvania Railroad E8s Join the T1 Trust

    Oct 30, 26 12:38 PM

    prr-e8-5761.jpg
    The T1 Trust has acquired former Pennsylvania Railroad E8A diesels 5702A and 5761A from the Fort Wayne Railroad Historical Society. They are bound for Cumberland.

    Read More

  28. Ligonier Valley Railroad: History, Roster, Timetable

    Oct 30, 26 12:03 PM

    ligonier-280-594.jpg
    The Ligonier Valley Railroad ran 10.5 miles from Latrobe to Ligonier, Pennsylvania. Opened December 1, 1877. Last day August 31, 1952.

    Read More

  29. Toledo, Peoria & Western Diesel Roster (All-Time)

    Oct 30, 26 10:25 AM

    47211399_2027303127561614_7742391129064079360_n.jpg
    Toledo, Peoria & Western diesel locomotives, each frame once. Thirteen Alcos, three Lima-Hamilton switchers, and 26 Electro-Motive units.

    Read More

  30. Toledo, Peoria & Western Steam Roster

    Oct 30, 26 09:14 AM

    tpw-280-10.jpg
    Toledo, Peoria & Western steam locomotives from the Rogers Consolidations of 1895 through the 4-8-4s of 1937

    Read More

  31. Toledo, Peoria & Western Railway: Map, Roster, History

    Oct 29, 26 11:12 PM

    28023048283766152h1j2860287098.jpg
    History of the Toledo, Peoria & Western. The Peoria & Oquawka, George P. McNear, the Santa Fe and Pennsylvania years, and the railroad that came back in 1989.

    Read More

  32. Cotton Belt Diesel Roster (All-Time)

    Oct 29, 26 07:58 PM

    12419291241256456126172538656.jpg
    St. Louis Southwestern diesel locomotives, each frame once. Baldwin switchers, F units, and new Cotton Belt-lettered power through the GP60s of May 1990.

    Read More

  33. Cotton Belt Steam Roster (Built Since 1900)

    Oct 29, 26 06:52 PM

    ssw-484-805.jpg
    St. Louis Southwestern steam locomotives built since 1900. Consolidations, Ten-Wheelers, and twenty class L-1 4-8-4s. The quantity column is 297.

    Read More

  34. Cotton Belt Railroad: Map, Logo, History, Rosters

    Oct 29, 26 10:56 AM

    663988500itcnvhgfjwo94857593.jpg
    History of the St. Louis Southwestern, the Cotton Belt Route. The Tyler Tap, Paramore's silver spike, the Thebes Bridge, the Blue Streak, and Southern Pacific control. Steam and diesel rosters are sep…

    Read More

  35. Pere Marquette Steam Roster (Built Since 1900)

    Oct 28, 26 11:54 PM

    1222109095utgklpop0597573892.jpg
    Pere Marquette steam locomotives built since 1900. Consolidations, Mikados, Pacifics, and 39 Berkshires. The quantity column is 503.

    Read More

  36. Pere Marquette Diesel Roster (All-Time)

    Oct 28, 26 11:48 PM

    9127348142681257926859027.jpg
    Pere Marquette diesel locomotives, each frame once. Two SW1s, 14 NW2s, three GE 70-tonners, eight E7As, and six BL2s delivered lettered Chesapeake and Ohio. The quantity column is 33.

    Read More

  37. Pere Marquette Railway: Map, Logo, Rosters, History

    Oct 28, 26 11:44 PM

    1010580949utbnnjotop959180993726ye.jpg
    History of the Pere Marquette Railway. Timber roads, the Prince years, the Van Sweringens, the Ludington car ferries, and the Chesapeake and Ohio merger of June 6, 1947.

    Read More

  38. Nickel Plate Road (Railroad): Map, History, Rosters

    Oct 28, 26 10:51 PM

    19058nkplpe870598u1yiu09085.jpg
    History of the Nickel Plate Road, the New York, Chicago and St. Louis. The Seney syndicate, the Van Sweringens, the Berkshires, and the Norfolk and Western absorption at 12:01 a.m. on October 16, 1964…

    Read More

  39. Nickel Plate Diesel Roster (All-Time)

    Oct 28, 26 10:48 PM

    q3958712571285236892368937904890.jpg
    Nickel Plate diesel locomotives, each frame once. Alco switchers and PAs, GP7s and GP9s, and the GP30s. The quantity column is 440. The 1950 fleet was 117.

    Read More

  40. Nickel Plate Steam Roster (Built Since 1900)

    Oct 28, 26 10:43 PM

    92384127461234727352786898398788.jpg
    Nickel Plate steam locomotives built since 1900, including the Lake Erie and Western, the Clover Leaf, and the Wheeling engines that took Nickel Plate numbers. The quantity column is 786.

    Read More

  41. EMD "E9" Locomotives: Specs, Roster, History

    Oct 28, 26 10:37 PM

    GMS4VzFXYAA3SBB.jpg
    EMD E9 cab units and boosters, 2,400 horsepower, built April 1954 through January 1964. Gear ratios, specifications, and the production roster by owner, serial, and order.

    Read More

  42. NYC 4-6-4 #5344, "Commodore Vanderbilt"

    Oct 28, 26 04:31 PM

    GK2FP3jXYAIVQpd.jpg
    NYC J-1e Hudson 5344, the Commodore Vanderbilt. Alco, November 1931. Carl Kantola’s shroud, December 1934, then a Dreyfuss bullet nose in 1939. Scrapped at Collinwood in 1954.

    Read More

  43. New Jersey, Indiana & Illinois Railroad: A South Bend Shortline

    Oct 28, 26 11:05 AM

    njii-nw2-2.jpg
    The New Jersey, Indiana & Illinois, the Jersey Line, ran from South Bend to Pine. Singer built it in 1905. Wabash stock control came in 1926. Two diesels, and the steam the record names.

    Read More

  44. Monon Diesel Roster (All-Time)

    Oct 28, 26 10:13 AM

    monon-f3s-emd.jpg
    Monon diesel locomotives, each frame once. F3s, nine BL2s, the C420s, and eight U23Bs. The quantity column is 96. The 1951 fleet was 57.

    Read More

  45. Monon Steam Roster (Built Since 1900)

    Oct 28, 26 10:09 AM

    monon-280-271.jpg
    Monon steam locomotives built since 1900. Twelve-Wheelers, Mikados, light Pacifics, and thirteen six-wheel switchers. The quantity column is 148.

    Read More

  46. Monon Railroad: Map, Photos, History, Logo

    Oct 28, 26 09:55 AM

    36386222_1923855317906396_2801775267905798144_n.jpg
    History of the Monon, the Hoosier Line. The New Albany & Salem, the X at Monon, Barriger's streamliners, and the Louisville & Nashville merger of July 31, 1971.

    Read More

  47. Missouri-Kansas-Texas Diesel Roster (All-Time)

    Oct 28, 26 09:48 AM

    83052935482357348683093748-090.jpg
    All-time diesel roster of the Missouri-Kansas-Texas. 406 locomotives, each frame once. Baldwin switchers, Alco cab units, F units, Geeps, and the SD40-2s.

    Read More

  48. Missouri-Kansas-Texas Steam Roster (Built Since 1900)

    Oct 28, 26 09:43 AM

    mkt-080-53.jpg
    Missouri-Kansas-Texas steam locomotives built since 1900. Moguls, Mikados, Pacifics, and the narrow-gauge shop tanks. The quantity column is 715.

    Read More

  49. Missouri-Kansas-Texas Railroad (Katy): Map, History, Rosters

    Oct 27, 26 11:02 PM

    69001098676156172u2u789800997.jpg
    History of the Missouri-Kansas-Texas, the Katy. The race into Indian Territory, Gould, the 1923 railroad, the Texas Special, and the 1988 sale. Steam and diesel rosters are linked.

    Read More

  50. Soo Line Diesel Roster (All-Time)

    Oct 27, 26 10:55 PM

    1098241824672157826892097.jpg
    All-time diesel roster of the Soo Line and the Wisconsin Central. 786 locomotives, each frame once. Cab units, Geeps, the Milwaukee Road engines, and the SD60s. The South Shore's 24 stay on that page.

    Read More

Sources

  • 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. Alco Locomotives. Minneapolis: Voyageur Press, 2009.