A total of 25 of these large engines were built. They were nicknamed "War Babies" by the AT&SF from being built and used during
World War II. The AT&SF ran the class from the mid-1940s to the mid-late 1950s. Despite being mainly freight haulers, their driving wheels were unusually tall for a "Texas" type, which led to them also being successful in passenger service.
Specifications Numbers 5011 to 5035, when built, were the largest and fastest class of
"Texas"-type locomotives ever built and equipped with
Timken roller bearings on every axle. The engines had a maximum output of measured at the rear of the tender, at a top speed of . , adjacent to the
California State Railroad Museum ==Present day==