As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUES FLT @ FL310 HYD 3 LO QTY EICAS ADV LIGHT ILLUMINATED HYD 3 QTY WAS @ 18% THEN DECREASED TO 14%, THEN BACK TO 16%. REMAINED AT 16% TIL LANDING. AFTER LANDING HYD 3 LO QTY MSG EXTINGUISHED AND NYD 3 QTY WENT UP TO 28%. REMOVED FROM SERVICE. REF W/O 341270 N/R -00001 FOR REPLACEMENT OF #3A HYD PUMP OPS CHECK GOOD NO LEAK NOTED. RETURNED TO SERVICE.