The SP articulated triple-unit diners

A famous part of Southern Pacific food service after 1939 was the articulated triple-unit dining cars, comprising a coffee shop and a dining car with a kitchen car between to serve both adjoining cars. Designed by SP and built by Pullman-Standard, there were initially two triple-units, assigned to the Daylight. A thorough history of these cars is provided in Volume 4 of the series, Southern Pacific Passenger Cars, covering Dining Service Cars (SP Historical & Technical Society, Upland, CA, 2010).

In 1941, SP would purchase two more of these triple units, and in 1949 another two, making  a fleet of six of these 3-car sets, normally used in Daylight, San Joaquin Daylight, and Shasta Daylight service, with occasional relief service  in the City of San Francisco. All cars were classified into Class AD (articulated diner).

Shown below is a Bruce Heard photo of the kitchen-passageway side of the second triple unit, SP 10253–10254–10255, in the San Joaquin Daylight. From left, the cars are the diner, the kitchen, and the coffee shop. Note that one of SP’s full-length dome cars is coupled at the left of the photo. The full-width diaphragms between cars of the triple-unit are  evident. 

The second pair of triple units built was quite similar to the first pair. Here is a builder view of the first of the two sets built in 1941, AP 10256–257–258, classes 70-AD-3, 57-AD-2, and 70-AD-4. Again, this is the kitchen-passageway side, with the high windows on the kitchen car.

These cars are iconic equipment for anyone interested in SP passenger service modeling in the transition era.  Awhile back, Broadway Limited produced a triple-unit model, which they chose from the second pair of these units, the 1949 ones shown above. Broadway  modeled SP 10259–269–261, which were classes 70-AD-3, 57-AD-2, and 70-AD-4.

Here they are on my layout with the coffee shop at right, coupled to an Athearn 77-C coach at right, and the new Rapido full-length dome car at left (I’ve posted about this car: https://modelingthesp.blogspot.com/2025/10/the-new-rapido-sp-dome-car.html ). 

Usual practice was to run the coffee shop forward in train consists, thus the implication that this train is moving to the right in the photo. But as I’ve mentioned several times, my layout’s staging is limited in length, preventing operation of prototypical-length passenger trains, so instead I operate the occasional deadhead move to balance passenger equipment between Los Angeles and San Francisco. In that sort of move, the triple unit could operate in either orientation, and the train shown above may be moving either direction.

 The Broadway Limited model is very nicely done, with effective design of the articulations between cars, including nicely-designed adjustments to the between-car diaphragms to permit operation on model-size curves. I have enjoyed including it from time to time in my operating sessions.

Tony Thompson