As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEARBOX RETURNED TO HAMILTON STANDARD FOR FAILED BORESCOPE REPAIR. AT DISASSEMBLY OF THE DRIVE (BULL) GEAR, HAMILTON STANDARD DISCOVERED THE TABBED WASHER WAS CRACKED. THE CRACK IS ADJACENT TO A TAB AND EXTENDS THROUGH TO THE INSIDE DIAMETER TAB. THE DRIVE GEAR RETENTION NUT REQUIRED 1,600 FEET/POUNDS OF TORQUE TO REMOVE. THIS PART SUPERSEDED P/N 775796-4.