B747-400
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Aircraft Equipment Problem Less Severe
Flight Crew Inflight Shutdown; Flight Crew Overcame Equipment Problem
Aircraft
About halfway into the flight; the CA (Captain) pulled up the engine page on the EICAS and we both noticed the Number 4 engine was down to 10 quarts of oil. This is odd since we took off with over 15 quarts on all engines. We decided to keep an eye on it. It got down to 8 quarts to where the EICAS turns magenta for quantity. There is no QRH reference for this. We informed Dispatch/[Maintenance Control] and advised if it gets too low we will do a precautionary shutdown. We pulled the power back to idle around that time at 8 quarts. We shut the engine down when it got to 5 quarts and about 3 hours left in the flight.Dispatch and [Maintenance Control] told us to continue to ZZZ and gave us a reanalysis for 1 engine inoperative. We could maintain our speed and altitude without a problem. It cost us about 2 kilograms of fuel with the engine shut down. During the descent we still had about 3 quarts of oil in Number 4 engine so we elected to do a restart via the QRH. We landed in ZZZ on all 4 engines without any problems and no other engine indications. We informed ATC initially after we shut the engine down and never declared an emergency.We need more guidance on engine oil quantity while airborne. How low is too low. When is it safe to do an engine restart. We have zero guidance on this stuff.
B747-400 First Officer reported an engine oil quantity anomaly resulting in a precautionary flight engine shutdown.