Plymouth built is first diesel in 1927, and it has been the country's most prolific small gas and diesel locomotive builder, with 7500 to date. Most of these are small mine and industrial locomotives of less than 25 tons. They are noted for their torque-converter locomotives, and almost all later production uses that type of transmission.⁽¹⁾

Plymouth is about 55 miles sw of Cleveland on the ex-B&O Sandusky - Mansfield line (Ashland RR operates this portion today).Also crossing the B&O just behind the shops is the Wheeling & Lake Erie (ex-Akron Canton & Youngstown RR). Most of the units were shipped out of here on the B&O. 1987 Gary Morris
Pine Creek RR 11 ton Plymouth #5, blt 1930, Allaire State Park, NJ 2002, ex-Marcus Wright Sand Co Bob Vogel	New Orleans Sewage & Water PlyJGT 12T #L4, New Orleans LA 1977, blt 1935 cn3802 Michael M. Palmieri	TTM 12 TON JCD Texas Transportation Museum, San Antonio TX 1993, blt 1936 cn5446 © Gary Stuebben	Kaiser Steel Co. DDT 12T #1021, Fontana CA 1972, cn6086 1958 Don Ross
Hesston Ply M6034-2 DDT 12T , Hesston Steam Museum, LaPorte, IN 2004, blt 1970 cn2926, nee Carpenter Steel Co, ex George Silcott's Loco Yd Stephen Brown	Ply JDT, Port of Sacraqmento CA 2004 Tom Hallendorf	ACF Ply JDT Steven A. Wydeck	EBT Ply JLC 14T , blt 1928, cn 2832 Lance Myers
Southern Wood Piedmont PLY JDT 16T, Augusta GA 1978	EBT Ply JDT NG 16T #M6, blt 1969 cn 6691, ex Warner Co. John Morgan	EBT Ply JDT NG 16T #M6, blt 1969 cn 6691, ex Warner Co. John Morgan	EBT Ply JDT NG 16T #M6, Orbisonia PA 2005, blt 1969 cn 6691 , ex Warner Co. Ellis Veech
East Broad Top Ply JCD 12T NG #M4, Rockhill PA 2004, blt 1947 cn5308, exx General Refractories, ex Warner Co Bill Waller	Plymouth 14T JCL	Huckleberry RR, Ply JCD 18T 36"ga #5, Flint MI 1984, cn#5503 F. Vollhardt - Don Ross	Bush Agri Resources Ply JCD 15T? #Miss Budweiser, Manitowoc, WI 1975 Ken Houghton
Harris Ply JCD 15T	Wheels of Time Ply JLB 16T #2, Peoria IL 2004, blt 1933 nee USA, exx CILCO, ex Allied Freight Jim Sands	H. J. Kaiser Sand & Gravel 16T JLC #3, Livermore CA Don Ross	Depeca Plymouth JHG 15T #76, Dennison OH 1977, ex Briggs & Turivas Moon Twsp PA, exx Armco, blt 1949 cn5449 John C. Benson
Carpenter Steel Plymouth DDT 15T #319 Tim Weidner	Plymouth DDT 15T #M04406, Plymouth Loco Works OH Tom Boylan	Plymouth DDT 15T , Plymouth Loco Works, OH Tom Boylan	Plymouth DDT 15T , Plymouth Loco Works, OH Tom Boylan
East Broad Top Plymouth 16T #M-5-A FrankVolhardt	Green Bay Ply DDT 15T? #92 Michael W. Bauers	Defence Logistic Agency Ply DDT 16T #85315, Ogden, UT 2005, ex Norfolk VA RJ Sorensen	Defence Logistic Agency Ply DDT 16T #85315, Ogden, UT 2005, ex Norfolk VA RJ Sorensen
New Orleans Sewage & Water Plymouth DDT 16T #L6, New Orleans LA 1983, blt 1977 cn7176 Michael M. Palmieri	Dupps Plymouth JLB 16ton #1, Germantown, OH, blt 1942, nee Ridgewood Forge Ordanance Plant #2, Watervliet NY Bill HH	Plymouth JLB 14T, Ford Museum, Dearborn MI 2003, blt 1927 David Haykus	Ply JLB 14T , Ford Museum, Dearborn MI 2006, blt 1927 Eric Larson
Morristown & Erie USA Ply JLC? 16T? #7299, Morristown, NJ 2006 Paul R. Tupaczewski	BN Ply JLC 16T, ND State RR Museum, Mandan, ND 2006, blt1928 cn2698, nee Northern States Power Mike Oestreich	Wilmington and Western Ry. Corp. [Historic Red Clay Valley] Ply JLB 18T #1, nee American Car & Foundry, blt 1942 Joseph C. Nelson	BO Plymouth 18T HL2 #25 Bob Redden
Wisconsin Sand & Gravel Plymouth HL-18, #2, Climax R6U, 1928 North Freedom WI Mid-Continent	Pine Creek RR Ply HL 18T Bobber Gibbs	National Lime & Stone Ply 18T HL #605, Carey OH 2002 David L. Miller	GATX Ply 18T JBL #1083 Tom Fassett
Plymouth HLA 18T	Plymouth HLA 18T	NH Wood River Branch RR Ply HLB 20T #1872[A100] , RI 1930, nee A100 cn2691 Walker Trans Collection - Bill MacIndoe	Cotton Plant & Fargo, AR Plymouth 18T HL #1 © Gary Stuebben
Cotton Plant & Fargo, AR Plymouth 18T HL #1 George Elwood	Hetch-Hetchy RR Plymouth HL 18T #1171, Mather CA 1947 Martin Hansen	Allaire State PK Plymouth 18T DLB Matt Conrad	Minn Mining Ply JDT 18T? , Little Rock AR 1985 Matt Ritchie
Mankato Scrap Yard Plymouth 18T JDT D.L. Owings	AFCO Ply JCD 18t #76, MAD River Museum, Bellevue OH Bill Waller	AFCO Ply JCD 18T #76, MAD River Museum, Bellevue OH 2004, ex AFCO, blt 1944 Bill Blomgren	MP Plymouth 18T MDT #1650 , Kansas City MO 1981, nee MP (NO&LC) 3003, on lease to Bartlett Grain Co,1957 cn6037 Todd Minsk
Lunkenheimer Valve Co. Plymouth JLB 18T, Buda 6-cyl, blt 1937 @Railway Expos #2 Mike Oestreich	Lunkenheimer Valve Co. Plymouth JLB 18T, Buda 6-cyl, blt 1937 @Railway Expos #2 Mike Oestreich	Wisconson Public Service Plymouth 18T JDT Gas-Hydraulic #702 Gary M. Collins	Amherst Industries Ply 18T JLK Waukesha 145-GK #14, Landisville, PA Ma & Pa HS
PP&L Ply 18T #1, Strasburg PA 2005, nee PPL Holtwood PA 1949, re-engined w/250 HP Mack Mike Carter	Strasburg Plymouth HL 20T #1, 1978. blt 1926 ©Harold Vollrath	Southern California Edison Plymouth 20T ML-6 #12, gas-mech 175hp LeRoi, nee USA12, blt 1941 Tom Fassett	Great Southern Plymouth HL 20T #4 Otto Perry
Coopersville & Marne Ply ML 20T#20, Coopersville MI 2002 Frank Hicks	Wolfboro Ply ML 20T #9, Wolfboro, NH 1975 ©Ed Hunt-GS	West Chester RR Ply ML 20T #1, West Chester PA 2006, nee USA, ex Hanson Quarry, Glen Mills PA, blt 1941 cn4146 Joe Jansen	J.I. Case Ply ML 20T? , Proviso IL 1970, ex Clausen Plant Racine WI Phil Soyring
Virginia Central RR Ply ML? NG #500, Fredricksburg VA 1975 ©Warren Calloway	Milwaukee Sewage Comm Plymouth 20T HLB #1 , ex Duluth Crushed Stone Co., cn2683 1927 Don Ross	West Badem & Southern Plymouth M #MX5 Bill Waller	Canada Crushed Stone Ply HLC 24T #7, Paikin (D) Hamilton ONT1982, blt 1927 cn2669, w/127hp diesel, ex TP&W 99 Gordon Strathdee % R.L.Kennedy
Canada Crushed Stone Ply HLC 24T #7, Dundas ONT, blt 1927 cn2669, w/127hp diesel, ex TP&W 99 Al Howlett % R.L.Kennedy	Mahoning Valley RR Heritage Ply EL 23T #320, Youngstown OH 2008 , ex Youngstown Sheet & Tube, blt 1940 cn4015 (only one ever built) Steve Timko	Muncie & Western Ply 24T HLB #2	Dufferin Concrete Prod. Ply HLB-3 #9114, D. Crupi & Sons, Scarborough ONT, blt 1928 cn2992, to St. Lawrence Cement Gordon Strathdee % R.L.Kennedy