[1]: 528  The Grand Trunk Western Railroad, a subsidiary of the Canadian National Railway, began offering commuter service on August 1, 1931.

[3] By 1971 the Grand Trunk estimated yearly losses at $241,626, leading it to contemplate increasing fares or canceling the trains altogether.

The coming of Amtrak and end of most private-sector intercity passenger service was then three weeks away but commuter trains were considered separate entities and remained in private operation after May 1, 1971.

SEMTA was charged to take over the ownership and operations of the fractured regional transit systems in Wayne, Oakland, Macomb, Washtenaw, St. Clair, and Monroe counties, including the city of Detroit.

[11] SEMTA's April 1983 timetable featured a stylized NYC Hudson locomotive on its cover and it continued to operate three weekday rush-hour round-trips, but all was not well.

[14][15]: 125 Throughout the 1970s and early 1980s SEMTA attempted to expand its commuter rail network as part of an integrated regional transit plan.

[16] SEMTA unveiled a smaller plan in 1977 for $1.2 billion in transit projects, to be partially funded by the federal government.

For commuter rail SEMTA allocated $42 million, both for the existing Pontiac route and to create service from Detroit to Ann Arbor and Port Huron, but not Plymouth.

[17] In 1979 the Michigan Department of Transportation commissioned a $350,000 feasibility study for the revival of passenger service over the C&O between Detroit and Lansing, the state capital.

[11] Passenger rail service resumed over the Grand Trunk on May 5, 1994, when Amtrak extended the Chicago–Detroit trains Twilight Limited and Wolverine to Pontiac.

[8]: 61  In May 1976 SEMTA acquired the old PRR Keystone trainset (the so-called "tubular train") from Amtrak for $80,000 but this equipment did not enter service.