What was found
A LOW FREQUENCY VIBRATION OCCURRED DURING FLIGHT AT 35,000 FEET WITH NO CHANGE WITH POWER INCREASES OR DECREASES OR CHANGES IN ALTITUDE. MAINTENANCE REMOVED AND REPLACED LEFT ENGINE.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
A LOW FREQUENCY VIBRATION OCCURRED DURING FLIGHT AT 35,000 FEET WITH NO CHANGE WITH POWER INCREASES OR DECREASES OR CHANGES IN ALTITUDE. MAINTENANCE REMOVED AND REPLACED LEFT ENGINE.