The St. Louis-San Francisco Railroad converted 10 of its older 4-6-2 Pacifics into 4-6-4 Hudsons. These Pacifics were built by the Baldwin Locomotive Works in 1917. Five of the conversions were completed in 1937, two more in 1940 and the last three in 1941. These 10 new oil burners were given road numbers 1060 through 1069.

Class 1060 (Locobase 165)

Data from 1947 and 1951 St L-SF locomotive diagram books supplied in May 2005 from the extensive collection of Allen Stanley. (Thanks to Chris Hohl for correcting the valve gear ID.) 1062, 1064-1066 were converted in 1937, 1063 and 1068 in 1940, and 1060-1061, 1067 in 1941.

Originally delivered in 1917 with Jacobs-Shupert fireboxes; see Locobase 8535. These leaked and were generally unsatisfactory. Only in 1937, however, were these rebuilt as the powerful 4-6-4s as shown here. Frisco mechanics substantially increased grate and firebox areas and the firebox heating surface was enhanced by one thermic syphon. Inside the boiler, installation of 10 more superheater flues in place of several dozen tubes resulted in an increase in superheater area of 240 sq ft (22.3 sq m). 13" (341 mm) piston valves supplied steam to the cylinders.

Rebuilds occurred as follows: 1062, 1064, 1065, 1066, 1069 in 1937; 1063, 1068 in 1940; and 1060, 1061, and 1067 in 1941. The 1951 diagram book notes that the class was "dismissed from service" between 23 October 1950 and 23 January 1952.