Bob,

This doesn't answer your question, but many railroads recognized the advantages of roller bearings on freight cars at least by the end of WWII. I have read that railroad management was slow to invest in roller bearing trucks on interchange cars because they saw them as mostly saving money on somebody else's railroad, and not at home.

The WP's first large order for roller bearing cars fit this philosophy. They were 29' mini-mill gondolas numbered 64001-6500, delivered by Greenville in 1953. These cars proudly carried the Timken "Roller Freight" herald when built. The short cars were only intended for U.S. Steel coil service between Geneva, Utah and Pittsburg, California. Cost savings and other benefits of roller bearings thus fell partly to the D&RGW, but mostly to the WP and their subsidiary Sacramento Northern.

The WP's next roller bearing plunge in 1956 was for ten PS-2 covered hoppers, 11201-11210, which were used for short distance limestone traffic to the Geneva furnaces. Curiously, 30 more PS-2 hoppers for the same service in 1958 numbered 11301-11330 had plain bearings. Go figure. These were apparently the last plain-bearing cars the WP ordered new.

In 1957, the WP bought 125 general purpose PS-1 50' double door boxcars numbered 35501-35625, and 100 more with auto loaders numbered 19601-19700. Both groups were equipped with roller bearings, though their truck frames had the usual hinged lids. The lids were painted bright yellow to mark the cars as roller bearing-equipped, a detail seen on some other roads about this time. From then on, except for the earlier mentioned PS-2s, all new WP cars came with roller bearings.

Yours Aye,

Garth Groff