As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEARBOX WAS REMOVED DUE TO FWU BORE DAMAGE. UPON INSPECTION OF CHIP DETECTORS, FOUND METAL ON BOTH PLUGS. AFTER DISASSEMBLY FOUND EXCESSIVE GALLING ON TM AND PIINION GEARS CAUSE FOR METAL. METAL CONTAMINATION WAS GENERATED FROM UNFINISHED MACHINING OF TM GEAR TEETH AT RADIUS. THIS CAUSED GALLING TO PINION GEAR. ASSURE PROPER MACHINING AND MESHING OF GEAR TEETH AND RADIUS AT FACTORY.