ALCO S-6

ALCO S-6
Type and origin Power type Diesel-electric Builder ALCO Model S-6 Build date May 1955 – December 1960 Total produced 126
Specifications Configuration: ​  • AAR B-B  • UIC Bo'Bo' Gauge 4 ft 8+1⁄2 in (1,435 mm) Length 45 ft 5 in (13.84 m) Width 10 ft (3.05 m) Height 14 ft 8 in (4.47 m) Fuel capacity 635 US gallons (2410 L) Prime mover ALCO 251A,B Engine type 4-stroke diesel Generator GE GT533 Traction motors 4 × GE 731 Cylinders straight 6
Performance figures Power output 900 hp

The Alco S-6 (spec. DL 430) was a diesel-electric locomotive of the switcher type constructed by ALCO of Schenectady, New York; a total of 126 locomotives were built between May 1955 and December 1960. The S-6 was a development of the earlier S-5; instead of the 800 hp ALCO 251 engine on the previous locomotive, the S-6 used a 251A or 251B engine rated at 900 horsepower. The locomotive rode on two-axle AAR trucks, giving a B-B wheel arrangement. A cow-calf version was produced exclusively for Oliver Iron Mining, who bought two: this was the SB-8/SSB-9 (DL-441).

Original owners

Railroad	Quantity	Road Number	Notes
ARMCO Steel	1	1202
Allied Chemical	1	110
Belt Railway of Chicago	1	420
B. Perini & Sons	1	101
Chihuahua Pacific	1	60	Renumbered 106
Cia Fundidora de Hierro y Acero	3	1–3
Ferrocarril del Pacifico	24	701–723
Ferrocarriles Nacionales de México	1	5300
Northern Pacific Railroad	1	750
Ohio River Company (ORCo)	1	56
Republic Steel	3	153,317,318
Secretaria de Comunicaciones de Obras Publicas (SCOP)	3	7133-1,2,3
Sheffield Steel	2	15,16
Southern Pacific Railroad	70	1033–1082,4634–4645
South Buffalo Railroad	6	40–45
Tennessee Copper	1	107
Upper Merion and Plymouth Railroad	1	61
U.S. Pipe and Foundry	1	38
Columbia Geneva Steel	1	1
Western Maryland Railroad	2	151,152
Ferrocarriles Unidos de Yucatan	1	301

References

• Sarberenyi, Robert. Alco S5, S6, and SSB9 Original Owners.