Specific Item Information: The “Western Pacific” was incorporated into the Union Pacific in 1983 as depicted by the road number on the locomotive UP 1983.

Model Information: Kato introduced the SD70 model in 2003. The first version was the SD70MAC. They followed up in 2005 with the SD70M. In 2006 they added the 'Flat Radiator' SD70M version. In 2009 they introduced the SD70ACe and revised the SD70M. All versions of this model share the same internal mechanism and only show minor differences in the shell. The internal mechanism was heavily revised/evolved in the 2009 release.

The revised versions are typical modern Kato release with a split-frame design, dual flywheels, chemically-blackened wheels and up-gradable to DCC with a drop-in decoder. They pull well and run quietly. The have very nice details like separately applied (rather than molded) hoses. Due the the 6-axle configuration, they do not run well in curves of less than 11 inches.