After World War I Rutland purchased a small batch of 4-6-2s to meet the demand of growing freight and passenger traffic brought on by the "Roarin' 20s" (and also to replace depleted power from the United States Railroad Administration control). The railroad listed these locomotives under the classification of K. While they primarily worked passenger trains, the heavy Pacifics were also assigned to priority milk runs, the lucrative business that sustained the railroad for several decades. They were the most powerful steamers it ever rostered outside of a few 2-8-2 Mikados, and later 4-8-2 Mountains. The units performed admirably for nearly three decades until pushed into retirement following the arrival of new diesels in the early 1950s.
Following the end of government control in March of 1920, through the United States Railroad Administration (USRA), the Rutland found its property and equipment in a state of complete destitution. This scenario played out on most other railroads across the country as companies attempted to pick up the pieces from the poorly executed and conceived USRA; many required months, if not years, to recover from the government takeover. The situation was made worse on the Rutland, which was seemingly always fighting some type of monetary troubles. Its only proper motive power at the time was a small batch of 2-8-2 light Mikados provided to it through the USRA in 1918. These locomotives were the most powerful the road had then rostered and performed faithfully until being retired in the early '50s.
However, aside from those units the Rutland rostered a rundown fleet of 2-6-0s, 4-6-0s, and 4-4-0s that dated as far back as the 1880s! The railroad did have some newer Ten-wheelers and Consolidations purchased between 1902 and 1913, under New York Central control, but even these were showing their wear after such heavy use during World War I. With traffic volume building in the 1920s, following a 1921 recession, the company was able to acquire a small fleet of new 4-6-2s between 1925 and 1929. As always these came from the American Locomotive Company's (Alco) Schenectady Works; numbered 80-85, they were given Class K-1 and K-2. The heavy Pacifics were as powerful as the Mikados, requiring rail of 95 pounds and offering tractive efforts of 43,000 pounds.
True to form, as Pacifcs were so often employed, Rutland used them regularly pulling top varnish, leading trains such as the Green Mountain Flyer and Mount Royal. However, they were also tasked with another important assignment, pulling milk trains. This business was of vital importance on the Rutland, particularly on a road that cherished every carload of freight and not blessed with heavy manufacturing centers so common in New England during those days. The movement of milk was also quite lucrative; according to Jim Shaughnessy's book, "The Rutland Road: Second Edition," it constituted more than $1 million in annual revenue in 1923 of the company's $6.695 million that year.
The white gold continued to hold steady at around $1 million annually throughout the decade. The Rutland would dispatch timed, scheduled unit milk trains that departed Ogdensburg and ran the length of the system before reaching Rutland, picking up shipments at creameries along the way (by then the consist usually boasted at least 40 cars of solid milk). From there it was split to reach the interchange at Chatham, New York where the New York Central handled the freight to New York or at Bellows Falls, Vermont where the Boston & Maine carried it into Boston. The "Roarin' 20s" also enabled the Rutland to purchase much need rolling stock and other equipment. Alas, though, these booming years would not last following the stock market crash in 1929 and succeeding depression.
The 1930s were hard on all railroads but especially the Rutland, which found itself in receivership after May 5, 1938. Efforts to save the system from total liquidation were far reaching, ranging from local citizens who formed the "Save The Rutland Club" to the state of Vermont, which eased its tax burden. The World War II years saw traffic rebound but the company did not exit receivership until November 1, 1950 when it became the Rutland Railway. Under new direction and management the road went to great lengths at streamlining operations. One way it did this was by retiring its fleet of tired steam locomotives, including brand new 4-8-2s purchased in only 1946. All, including the Pacifics, were used to help pay for 15 new diesel road-switchers from Alco which arrived between 1951 and 1952. The last 4-6-2 was retired and scrapped in early 1953.