Dynamometer Car at the California State Railroad Museum

Photo by Cliff West

Southern Pacific Dynamometer Car #137 was built in 1926 by Standard Steel Car with dynamometer equipment and instrumentation from the Baldwin Locomotive Works. Designed to measure the performance of steam locomotives, it was assigned to the Motive Power Department but was also used for freight car testing. In the 1950s it was equipped with new instrumentation for diesel locomotive measurements. As measuring technology advanced, the car eventually became obsolete. It was retired in December 1975 and was donated to the California State Railroad Museum in Sacramento, California, by Southern Pacific in December 1979.