Empty tank car train of the Utah Railway rolling down Soldier pass on the heavy 2.4 % grade below the Nolan tunnels, with MK50-3 (built by MK Rail in Boise, Idaho as MK5000C in 1994) # 5001, # 5002, SD50S # 6062, SD50S # 6064 (in the orange G&W paint scheme) and MK50-3 # 5004.