It was the first streamliner with sleeping cars and the first of the Chicago-to-Coast streamliners; its 39 hour 45 minute schedule became the standard. (In April 1935 the fastest train took 59 hr 20 min Chicago to Portland.) The M-10001 was withdrawn in 1939 and replaced with another articulated trainset (but still just one). The train was the first of the 40-hour Coast streamliners to run daily, in February 1947. In 1955 the Milwaukee Road replaced the Chicago and North Western between Chicago and Omaha; from January 1959 until 1967 the train ran via Denver. The train was discontinued May 1, 1971, with the start of Amtrak. The route roughly follows the trail of the defunct Amtrak route, the Pioneer.