Starting in 1969, Santa Fe bought twenty GE U23C’s for service on unit sulfur trains in Texas, where their hefty pulling power could be put to good use. But by May, 1973, when the 7904 and three companions were hauling northbound freight on the Albuquerque-El Paso line near Belen, most were assigned to New Mexico, Colorado and Kansas service, including Raton Pass. Few U.S. roads acquired the 2300-hp units, which were intended mainly for hump power and transfer drags. But a Brazilian ore-hauler bought 20 and liked them so well that 150 more were built there under license. Santa Fe’s were to remain on the roster for 15 more years before being returned to GE and sold for scrap.