The Pioneer ran until May, 1997
Prior to July 1983, the Pioneer joined the California Zephyr at Ogden.
For a time after July, 1983, the Pioneer continued to Salt Lake City, and joined the California Zephyr there, before its terminal was shifted to Denver
Salt Lake City (Grant Tower) to Ogden
In later years, the Pioneer ran through from Ogden to Denver before joining the California Zephyr
The Pioneer continued east to Chicago, as part of the California Zephyr, Trains 5 & 6