Sitting in the backshop of Santa Fe’s San Bernardino Shops are half of the railroad’s TR4 "cow and calf" sets: TR4A 1418L and TR4B 1418A. Having worked most of their lives in Argentine Yard in Kansas City, Kansas, they are in San Bernardino awaiting rebuilding into SSB1200s. These engines, essentially a paired set of SW7 switchers but built as A- and B-Units , drawbarred together, carried numbers similar to the Santa Fe’s cab diesels (F-Units, E-Units, PA-1s, etc.) in that the lead engine’s road number ends with an L (for “Lead”) and the cabless unit’s number ends in an A. Built by EMD’s Cleveland, Ohio, plant in June 1950 as EMD Demonstrators 2418L/2418A, and sold later that year to ATSF as 2418L/2418A, these were renumbered 1418L/1418A in 1974 or 1975. This set was later rebuilt by the ATSF into SSB1200A 1242 and SSB1200B 1243, and were eventually sold to US Steel as USSX 5A/5B. (San Bernardino, California – January 1979)
