Like many other American railroads, the Delaware & Hudson Railway (D&H) at the start of the Sixties displayed little remaining interest in its most famous passenger trains, the "Montreal Limited" (an overnight train) and the "Laurentian" (a daytime train) between New York City and Montreal in Canada. In 1964 the D&H even announced the discontinuation of both of their prestige trains. However, the outcry was great and the railroad bowed unwillingly to the demands of its passengers. In 1967, Frederic "Buck" Dumaine became the new president of the D&H. He was a great supporter of passenger service and began immediately to buy up used rolling stock in order to spruce up these rolling advertisements for the D&H. Four ALCO PA1 diesel locomotives (as D&H road numbers 16 - 19) were acquired from the Atchison, Topeka, and Santa Fe Railway (ATSF) and different passenger cars were acquired from the Denver und Rio Grande Western Railroad (D&RGW). Repainted into the unmistakable blue-silver-yellow paint scheme of the D&H, both of these prestige D&H trains brought back once more the great flair of the great era of long-distance passenger trains. In 1971, most of the long-distance passenger trains were taken over by the newly established government railroad Amtrak and along with them the D&H trains between New York and Montreal. Amtrak decided however to cancel these trains, and the "Laurentian" made its last run on April 30, 1971.
Yet, in 1974 the locomotives and cars experienced a renaissance, when Amtrak decided to offer a passenger train again between New York and Montreal. With the motive power and rolling stock provided by the D&H, a passenger train on this route ran for the first time again on August 5, 1974, now under the name "Adirondack". The D&H had its four ALCO PA1s modernized specially for this. This was done by Morrison-Knudsen, whereby the maintenance-intensive 16-cylinder diesel motors (type 244) were replaced by improved 12 cylinder motors (ALCO model 251). Among railroad enthusiasts moreover the ALCO PA units were rated as the most beautiful and aesthetic diesel locomotives that had ever been built. These modernized locomotives pulled the "Adirondack" with its D&H rolling stock until March of 1977. From this time on Amtrak took over the "Adirondack" with its gas turbine powered "Turboliners".