"Z" trains are the highest priority freight trains on the BNSF Railway. At Cajon, California, on July 27, 2019, BNSF Z-WSPSBD9-25, a hot Priority UPS-LTL Intermodal train operating from Willow Springs IL to San Bernardino CA; is on Cajon Pass' Main 2 and has met eastbound BNSF Intermodal Stacks S-SDGMEM1-26 coming out os San Diego for Memphis, and which is comprised of only autoracks at this point. (Intermodel cars will be added at Belen, New Mexico, en route.)