Southern Pacific Class GS-4

Southern Pacific Class GS-4

The GS-4 was a streamlined 4-8-4 Northern type steam locomotive used on the Southern Pacific Company from 1941 to 1958. They were built by the Lima Locomotive Works and were numbered 4430 through 4457. GS stands for "Golden State" or "General Service."

Unlike the GS-3, the GS-4 had a dual-headlight casing (top headlight was a mars light) on the silver smokebox. Another change was the all-weather cab. It retained the skyline casing atop of the boiler, skirting on the sides, an air horn, teardrop classification lights, and whistles. They carried the orange and red "Daylight" paint scheme.

The GS-4s were passenger engines capable of 110 mph (180 km/h). (Timetable speed limit never exceeded 75 mph.) Southern Pacific's premier passenger trains were pulled by GS-4s, the Coast Daylight, San Joaquin Daylight, Lark, Cascade, Golden State and Sunset Limited. During wartime and in the first years after the war some of the GS-4 locomotives were painted black; by 1948 all had been repainted into Daylight colors. Starting in March 1950 most were painted black again and had their side skirts removed for easier maintenance, and were re-assigned to the San Jose-San Francisco commute trains, freight service and the occasional San Joaquin Daylight (steam locomotives remained on that train as late as 1956 which made the San Joaquin Daylight the last streamliner train to be pulled by steam on the Southern Pacific) until new diesels arrived and they were retired. The last GS-4 engines were deskirted and painted black in 1956; a GS-4 pulled its last passenger train in January 1957. All were retired by 1958. GS-4 number 4443 pulled one of the final steam excursions on the Southern Pacific in 1957.