EMD SD70ACe-T4 No. 3035 leads the last MRONY (Roper Yard in Salt Lake City to North Yard in Denver) freight across the overpass over Colo. Highway 72 at the west end of Leyden, Colorado, on December 8, 2018. Amazingly, after all the years since Rio Grande slowly melded into Southern Pacific and disappeared into UP, the bridge here still shows the “heritage” of the Moffat Tunnel Route. A side note—only on the shortest days of the year in December and January is the Rio Grande logo fully illuminated during midday hours.
Tier IV locomotives are the safest, cleanest, and most fuel efficient locomotives on the rails today. Unfortunately, most of them are ugly and are as quiet as an ACS-64.
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.