What was found
(CAN) ENROUTE PILOT NOTICED THE OIL QUANTITY WAS AT ZERO ON THE NR 1 ENGINE - BOTH OIL PRESSURE AND OIL TEMPERATURE WERE NORMAL. SHORTLY THERE AFTER THE OIL PRESSURE STARTED TO FLUCTUATE AND THE OIL PRESSURE WARNING LIGHT ILLUMINATED.FLIGHT CREW SHUTDOWN NR 1 ENGINE. AIRCRAFT DIVERTED AND PERFORMED AN ABNORMAL LANDING - AIRCRAFT LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTION REVEALED THE BANJO FITTING BLOWN OUT FROM THE GEARBOX CAUSING THE OIL LEAK.MAINTENANCE REPLACED THE GEARBOX, GROUND CHECKED THE ENGINE AS SERVICEABLE - NO LEAKS TO REPORT.AIRCRAFT RETURNED TO SERVICE WITH NO FURTHER INCIDENTS TO REPORT.