Pacing Union Pacific Big Boy

READ FIRST:
Having just come down through the Canyon Sub into Oroville, the 4014 runs the final few dozen miles towards Sacramento and Roseville, where it will be on display for two days before running back east over Donner Pass. Enjoy and stay tuned =)
Consist is about 1,265 tons behind the main tender, including the diesel & water cars. Speed here is ~45 mph.
FAQ (Read before commenting):
The water overflow from just in front of the rear cylinder on the fireman's side is the exhaust steam injector overflow port. Discharge from this port is normal when starting and stopping the injector, and when the injector switches between live steam and exhaust steam.
The diesel locomotive, while no longer necessary for PTC compliance, will continue to periodically be used where it is expedient for steam locomotive fuel conservation and assistance on long, sustained grades (power / dynamic braking).