A westbound Santa Fe freight has descended Cajon Pass and is just north of San Bernardino. The lead unit has been rebuilt into an SD45u and is teamed with a cowl unit in the "Kodachrome" merger scheme and another SD45.
The EMD SD (special duty) series are a strong and reliable kind of locomotive which still serve America's rails today. They have proved themselves reliable by clocking in several million miles of freight service over several decades.