What was found
ELEVATOR HAS BUFFETING AS AIRSPEED INCREASES. WHEN THE AIRPLANE IS BANKED AND ELEVATOR BACK PRESSURE IS APPLIED, BUFFET INCREASES, ON FINAL APPROACH FOR LANDING, FULL FLAPS, SPEED 160KTS BUFFETING IS ALSO FELT IF ELEVATOR BACK PRESSURE IS APPLIED. NOTE: PTC ON OR OFF HAS NO EFFECT. WITH THE BUFFET THERE IS AN UNEXPLAINED HARD INPUT TO THE ELEVATOR, USUALLY NOSE DOWN. CONTROL YOKE USUALLY MOVES 3 TO 5 FORWARD. REMOVED AND REPLACED BOTH LEFT AND RIGHT HAND ELEVATOR DAMPER UNITS. LEAK AND OPS CHECK GOOD IAW MM 27-30-5.