The rolling stock collection of the California State Railroad Museum is extensive, spanning the period between 1874 and 1950. It ranges from the prosaic caboose to the lavish private car, and includes freight as well as passenger equipment. The rolling stock collection is central to the Museum's interpretation of such key facets of railroad history as the transportation of the U.S. mail by rail, the role of refrigerator cars in revolutionizing the American diet, sleeping cars and the romance of long-distance train travel, and dinner in the diner. Some coaches are exquisite examples of the nineteenth-century car builders' art, while cars from the 1920s still roll on the Sacramento Southern, the Museum's excursion train ride line along the Sacramento River. In addition to its passenger and frieght roster, the Museum maintains a fleet of 17 maintenance-of-way cars dating from 1905 to 1974. These include cranes, scale test cars, tool and outfit cars, flangers, snowplows, dynamometer cars, and a fire truck on rails.
While the rolling stock collection of the California State Railroad Museum is extensive, only a portion is on public exhibition at any one time. The remaining cars are either undergoing restoration or awaiting restoration at the Museum's shop facilities.