What was found
THE CREW NOTED THAT THERE WAS A VIBRATION IN THE CONTROL YOKE. VIBRATION BEGAN IN THE LOW 30,000'S AND CONTINUED IN CLIMB TO 35,000. VIBRATION SEEMED MORE PRONOUNCED AS AIRCRAFT ACCELERATED, VIBRATION DECREASED MARKABLY BELOW 30,000 FT, COULD ALSO FEEL VIBRATION ON FLOOR. A/C RETURNED TO IAH AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED ELEVATOR HINGE POINTS AND FOUND THAT LT ELEVATOR BEARING TIP TORQUE TUBE HOUSING LOOSE. MAINTENANCE REMOVED AND REPLACED LT ELEVATOR TORQUE TUBE TIP BEARING HOUSING, PERFORMED ELEVATOR DEFLECTION CHECKS, NO DEFECTS NOTED AND AIRCRAFT WAS RELEASED FOR TEST FLIGHT PURPOSES ONLY. TEST FLIGHT WAS SATISFACTORY, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.