exceptionally high availability for service. Such positives had led the class to being excellent performers. An S-2 can make the 512 mile round trip from Whitefish to Havre and back with only minor work at Havre, such as refueling and greasing. 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. On flat, straight track, an S-2 is capable of hauling 18 heavy steel Pullmans at . Their power and speed allowed them to make up nearly an hour with an all-steel passenger train on the Montana division and Spokane division. All S-2s were delivered in the Glacier Green paint scheme except for No. 2577, which carried a coat of light grey or aluminum paint on the boiler and cylinder jackets at delivery, most likely for photographic purposes. It was eventually repainted to Glacier Green, matching the rest of the class. All engines came with chrome plated cylinder covers and steam chest heads and by the 1950s, all engines had received the more economical all-black paint scheme. The only major rebuilding of the class was the replacement of the original bearings with Timken roller bearings on every axle in 1945. Some engines were temporarily converted to burn coal for a period in the late 1930s, with the tender having a capacity of 24 tons of coal. Vestibule cabs were added to engine 2577 in the early 1930s and engines 2582, 2586, 2587 and 2588 by the late 1940s. Revenue service 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. They have also traversed over the famed Marias Pass. As a result of their speed and high availability for service, they proved to be reliable locomotives, running up to approximately a month. 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, then in 1931, they were tested in pulling the Empire Builder over the Divide between Havre and