As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) M/R TRANSMISSION RECEIVED FOR INSPECTION. DURING VISUAL INSPECTION, IT WAS NOTED THAT THE INPUT PINION HAD UNCOMMON DAMAGE TO THE DRIVE SPLINES. SUBMITTER SUGGESTED CAUSE COULD BE INCORRECT SHIMMING OF ATTACHING PARTS OR LOSS OF TORQUE TO THE NUT (PN 369A5513). MANUFACTURER''S SERVICE BULLETIN COULD POSSIBLY CORRECT THIS PROBLEM.