DSSA Eastbound Freight Service 9-29-1956
SOO Condensed Fast Freight Schedules 2-1-1960
SOO Condensed Fast Freight Schedules 4-1-1964 – also see a Freight Train Schematic map based on this schedule
SOO Freight Schedules 1-1-1987
SOO Sprint Schedule 4-1988
SOO SP D&RGW Freight Schedules 1989 – Soo Line, SP, and D&RGW schedules from SP’s proposal to purchase the Kansas City to Chicago route.
Soo Line Online has several employee timetables available and wx4.org has one. These are useful as the train numbers and times seem to correspond to the trains that actually ran, which is not always the case with all railroads.
The Soo Line History group at groups.io has a 1965 Eastern Division blocking book and 1982 Schiller Park blocking instructions available in their files section.
Railroad Paper Collectibles has freight schedules available from 1986.
Fred Hyde’s 1993 Soo Line Review book has a summary of trains operated as of June 1, 1993 as well as some additional information about the coal trains of that time.