RDC #712 at the Anchorage Shops (May 10, 1988)
Photo courtesy of E.D. Motis

The Budd Co. constructed 404 Rail Diesel Cars (RDC) for 27 railroads and 4 foreign countries from 1949 to 1962. Five different models were offered: RDC1 (full coach), RDC2 (combination baggage-coach), RDC3 (Railway Post Office, baggage, coach), RDC4 (RPO-baggage), and RDC9 (full coach, but without operating controls). Each RDC is powered by two 275 h.p. General Motors diesel engines (except the RDC 9 which uses one) mounted under the floor. Currently, there are less than 50 RDCs in operation and they can be found in Texas, New York, Pennsylvania, New Jersey, Ontario and Alaska.

The Alaska Railroad has four RDCs numbered 701, 702, 711 and 712. Numbers 701 and 702 were rebuilt along the lines of the BCR units. They have 300hp Cummins, 6cyl.and Voith transmissions. Numbers 711 and 712 were re-engined with 300 hp Cummins, but retain the original Allison transmission. Numbers 701 and 702 were built as RDC4 converted to RDC2 by NH&H then reconverted from RDC2s and have larger baggage areas than the RDC3 711 and 712. (1/27/99)

Thanks to Frank Dewey for providing this information

Added 10/18/08: "The Budd RDCs went to Fairbanks for their annual inspections and maintenance. It was determined their electrical problems were just too costly to be repaired economically so they are all going to be retired immediately. All four have made their last revenue trips and now will be put out for bid."

Added 2/27/09: No. 712 has sold to Eagle Cove Camp & Conference Center, Inc. in Tomahawk, WI.

Added 10/5/17 by Dave Schauer: The RDC is leased to the Lake Superior Railroad Museum from a church organization in Wisconsin that hopes to move it there in the future, but for now it is still in Duluth and used on tourist trains (pulled, not self-propelled). 

ex-ARR RDC #712
Photo line snaps shots as a former Alaska RDC rolls past lettered as the DM&IR's RDC that ran over these same tracks. North Shore Scenic Railroad, Palmers, Minnesota, 9/7/13.
Photo courtesy of Dave Schauer

Added 10/19/17 by Bill Edgar: To my knowledge the North Shore Scenic owns it. 

ex-ARR RDC #712
A former Alaska Railroad RDC2 brings up the rear of a North Shore Scenic Railway excursion train as it leaves downtown Duluth for a trip along the shore of Lake Superior.
Below Fitgers Brewery, Duluth, Minnesota, 9/17/17
Photo courtesy of Bill Edgar