As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED A STRANGE INTERMITTENT VIBRATION. DURING A VISUAL INSPECTION, THERE WERE CONTACT MARKS ON THE LT AFT CORNER MOUNT UP STOP/SAFETY WASHER. UPON INSPECTION WITH THE CORNER MOUNT LIFT TOOL, THE LT AFT CORNER MOUNT WAS FOUND SEPARATED. ALL 4 CORNER MOUNTS ARE ABLE ENGINEERING O/H COMPONENTS CHANGED TOGETHER 309.0 HOURS EARLIER. ALL 4 MOUNTS WERE CHANGED.