Excerpt from Wikipedia:

The El Capitan was a streamlined passenger train operated by the Atchison, Topeka and Santa Fe Railway (“Santa Fe”) between Chicago, Illinois, and Los Angeles, California. It operated from 1938 to 1971; Amtrak retained the name until 1973. The El Capitan was the only all-coach or “chair car” (non-Pullman sleeper) to operate on the Santa Fe main line between Chicago and Los Angeles on the same fast schedule as the railroad’s premier all-Pullman Super Chief. It was also the first train to receive the pioneering Hi-Level equipment with which it would become synonymous.