No. 137 on a works photo
Baldwin / collection Taylor Rush
After some 0-6-0 switchers, which the Southern Pacific had received from several manufacturers, they built more in their own shops. Six of the class, designated S-12, were built between 1919 and 1921 in Los Angeles and 32 in Sacramento. At least some of the locomotives were oil-fired, as the technical data shows. Their service ended between 1949 and 1952.