As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE PILOT OBSERVED LOW/ERRATIC OIL PRESSURE AND TORQUE INDICATIONS AND EXECUTED A PRECAUTIONARY LANDING. A LARGE OIL LEAK WAS FOUND FROM THE EXHAUST STACK (GEARBOX VENT) AND COMPRESSOR VENT ORIFICE. THE ENGINE GEARBOX WAS FOUND TO HAVE MORE OIL THAN NORMAL IN IT. A PROBLEM WITH THE GEARBOX SCAVENGE OIL SYSTEM WAS SUSPECTED AND THE GEARBOX WAS REPLACED AND SENT FOR REPAIR. NO FURTHER PROBLEMS.