As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE ENGINE CHIP DETECTOR LIGHT ILLUMINATED IN-FLIGHT. THE TEAR-DOWN INSPECTION OF THE ENGINE REVEALED THE NR 3 AND NR 4 PINION BEARINGS ROLLER CAGES WERE EXCESSIVELY WORN. THESE BEARINGS ONLY HAVE 489.1 OPERATING HOURS SINCE NEW. THE OPERATOR BELIEVES THE 'NEW STYLE' BEARINGS ARE MADE OF A SOFTER MATERIAL.