The locomotives were built to haul passengers on the GN mainline, pulling the Empire Builder and the Oriental Limited and were assigned to the Montana division for service between Williston, North Dakota and Havre, Montana and the Spokane division for service between Spokane, Washington and Wenatchee, Washington, then assigned to the Divide between Havre and Whitefish, Montana, of which mostly runs through the famed Marias Pass, though they were also used on GN tracks outside of their assigned areas.

Intended for fast passenger service, the S-2s were built lighter and with larger driving wheels than the earlier S-1 Class of "Northerns" of 1929.

In addition to being fast, they were also economical in fuel consumption and maintenance expenses and had an exceptionally high availability for service.

However, it was not unusual for an S-2 to run the 566 mile distance from Whitefish to Williston, North Dakota and have the locomotive detach from its train at Havre only for refueling.

2577, which carried a coat of light grey or aluminum paint on the boiler and cylinder jackets at delivery, most likely for photographic purposes.

[3] The S-2s spent most of their career pulling the Great Northern's passenger trains, such as the Empire Builder and the Oriental Limited between St. Paul and Seattle (Chicago-St. Paul portion uses Chicago, Burlington & Quincy's mainline), but have also pulled fast mail trains.

As a result of their speed and high availability for service, they proved to be reliable locomotives, running up to approximately 20,000 miles (32,000 km) a month.

[5] Initially, nine were assigned to the Montana division for service between Williston, North Dakota and Havre, Montana, and five were assigned to the Spokane division for service between Spokane, Washington and Wenatchee, Washington due to both divisions having long tangents, easy curves and light grades,[6][1] then in 1931, they were tested in pulling the Empire Builder over the Divide between Havre and Whitefish, Montana.

It was then retired in December 1957 and on March 21, 1958, the Great Northern had decided to hold it for historical purposes and it was eventually repainted to its original Glacier Park paint scheme.