As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DISASSEMBLY OF GEAR CASE REVEALED THE TAB WASHER AND RETAINING RING ON THE FORWARD RIGHT IDLER GEAR BROKEN. BROKEN BEARING (P/N 775765-2) IN SLIDER BLOCK ASSY. INPUT PINION GEAR WORN. METAL CONTAMINATION LOCAL TO THIS AREA. HSS SO NR 86314 SE. CUST: WINGS WEST A/L