UP SD70M's 3957 and 5172 did not have enough power to lift the 7000+ ton SBRHGW-15 (Special-Brighton, CO-Harlingen,TX-Windmill) train up the grades of Colorado's Joint Line. They were forced to stop at Castle Rock and pick up BNSF 5925, the protection unit kept there, to make it to the summit at Palmer Lake. Under a Colorado sky, the train is seen heading Southbound through Larkspur on Main #1.