In 1949 it launched a revolutionary new self-propelled passenger coach, which it called a rail diesel car (RDC). Between its production line period for RDC's between 1949 and 1962, Budd built 398 of the RDC’s. Because they had operating controls at both ends, the use of a turntable or Y track was unnecessary to turn the train around. Another advantage was they came equipped with two diesel engines. Should one fail, the second was sufficient to get the rail car to its destination.

Canadian Pacific Railway acquired RDCs as its last ditch attempt to remain competitive in the intercity rail passenger market.  When Via Rail was formed by the Government of Canada in the 1970s, most of Canadian Pacific Railway’s remaining Dayliner fleet was transferred to the Crown Corporation.

CPR retained a handful of Dayliners including 9108. The car was transferred to Sudbury where it was used to transport railway personnel in Northern Ontario. It was also renumbered RDC 91. The flexibility of RDC 91 allowed the railway to move various elected officials and media around the region in a massive Communications Program designed to show railways were an integral part of the Canadian economy and an environmentally sound and safe means of moving goods across the country. In 1981 RDC 91 along with other display cars was used across Ontario to help mark the railway's 100th founding anniversary.

In Sept. 1984, RDC 91 was brought out West to move media and dignitaries to a special ceremony in the heart of Rogers Pass, BC to mark the beginning of the railway's double tracking mega-project through the Selkirk Mountains. This was the first time a rail diesel car had ever operated independently from Lake Louise to Revelstoke.

In 1996 when Canadian Pacific Railway moved its headquarters to Calgary, the decision was made to bring RDC 90 and 91 as well. The intention was to refurbish the cars and put them in the original livery and use them for both public affairs duties as well as for employee events.The cars were put into storage and never restored as intended.

Stored at the company's shops in Calgary, the decision was made to try and find suitable museums for Canadian Pacific Railway’s last two RDCs. RDC 90 was renumbered to its original 9069 and is located at The Canadian Museum of Rail on the outskirts of Montreal. RDC 91 likewise has been renumbered 9108 and operates at the Alberta Central Railway Museum.