As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENROUTE, THE NR 4 HYDRAULIC SYS LOST BOTH PRESSURE AND FLUID QUANTITY. THE FLIGHT CREW DECLARED AN EMERGENCY TO ALLOW FOR ALTERNATE GEAR EXTENSION OF THE WING GEAR. THE LANDING WAS UNEVENTFUL. MX FOUND THE NR 4 ENGINE DRIVEN HYD PUMP LEAKING FROM THE CASE DRAIN AND REPLACED IT. SYS OPERATION WAS NORMAL AFTER THE PUMP WAS REPLACED. (K)