Acquired by the St. Louis–San Francisco Railway in the mid-1940s, the GE 44-ton switchers (fleet series #4–#8) were built specifically to skirt union firemen requirements on sub-90,000 lb locomotives. Powered by dual Caterpillar D17000 diesels turning GE traction gear, these center-cab units were assigned to light industrial switching, grain elevator spurs, and low-density branchlines where road switchers were overkill or bridge weight restrictions applied. Dressed in Frisco’s classic black-and-yellow scheme sporting the coon-skin herald, they handled terminal chores and local transfers across Missouri and Kansas until diesel fleet modernization sidelined them by the mid-1960s.