As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, AT 310 KTS, FELT AN AIRFRAME VIBRATION. FLIGHT ATTENDANT IN REAR GALLEY CALLED AND SAID BACK OF PLANE WAS VIBRATING BADLY. LEVELED OFF AT FL 320 AND SLOWED THE ACFT TO 74 AND VIBRATION WENT AWAY, SLOWLY INCREASED SPEED TO .8 WITH NO FURTHER PROBLEMS. ACCOMPLSUHED TSM PROCEDURE 27-30-00-810-850-A. REPLACED INBOARD GREEN SYSTEM SERVO CONTROL ELEVATOR IAW AMM 27-34-51-0901. ADJUSTEDMENT AND TESTED OK.