As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED EXCESSIVE LOSS OF OIL AND LOW OIL PRESSURE ON RT ENGINE. DISASSEMBLY OF TURBOCHARGER REVEALED THE 3 GROOVES ON THE INBD THRUST BRG WERE MACHINED INCORRECTLY. THEY ARE TOO LARGE TO THE EDGE OF BEARING ALLOWING OIL TO BYPASS. BEARING PIN 407262-000.