In 1902, the Northern Pacific purchased its last major group of ten wheelers, forty Class S-4 Vauclain compound engines built by Baldwin for the price of $16,787.59 in 1902 dollars. As built, the Vauclain compound drive cylinders were very efficient, but a maintenance nightmare. Therefore in 1924 all S-4s were converted to simple drive cylinders. Five years later superheaters were added. Following this they were very successful engines, with most serving more than fifty years until the end of steam. Crews liked the S-4s because they were well-suited to branch line service, were smooth-riding, powerful, and easy to fire.
The 1364, assigned to the Tacoma Division, was requested to do service in the Seattle Division in 1931 to run between Arlington and Black River. She was also seen in the eye of a camera at Seattle around July of 1932. In 1942 in the Auburn yard a brakeman for the 1364 twisted his ankle, At that time the 1364 was hauling 3 cars of mail from Seattle to Auburn.