Otto wrote: <There is photographic evidence of GN jennies in ore service on Cajon <Pass in California during the winter of 1951/52, carrrying Utah ore to <Kaiser Steel in Fontana, Cal. I wonder whether this could have been a <seasonal arrangement with the GN??? (We do know Santa Fe crews did not <like the shorty cars with wheels protruding beyond the frames and the <"arrangement" did not last too long).
After the closure of the Yosemite Portland Cement Company in 1944, the Yosemite Valley Railroad sold their 51 ex-GN hopper cars (called rock cars on the YV) to various other railroads including 32 which were sold to Kaiser. Those would have been the ones in ore service on Cajon Pass....