What was found
CLIMBING THROUGH 8,000 MSL AT 250 KTS, NOTICED AILERONS WERE MORE DIFFICULT TO MOVE THAN NORMAL, AS WE CLIMBED AND INCREASED AIRSPEED TO 290 KTS THE AILERON CONTROLS GRADUALLY BECAME HARDER TO MOVE AT APPROX 20,000 MSL AND 290 KTS AILERONS BINDING FEEL AND WHEN TRIED TO RETURN TO CENTER YOKE SNAPPED BACK TO CENTER WITH ROUGHLY 2 INCHES OF TRAVEL IN YOKE. THIS WAS EXPERIENCED WITH BOTH CAPTAIN AND FO`S YOKE. IN DESCENT THESE CONDITIONS GRADUALLY REVERSED TO NORMAL AILERON CONTROL WITH THE YOKE. PERFORMED TSM TASK 27-10-00-810-803-A AND FOUND AUTO PILOT SERVO ACTUATOR BINDING. REMOVED AND REPLACED AUTO PILOT SERVO ACTUATOR IAW AMM 22-11-04, OPS CHECK NORMAL. PERFORMED AILERON ELECTRONIC RIGGING IAW AMM 27-03-02, ALL CHECKS NORMAL. PERFORMED AILERON TORQUE TUBE INSPECTION AND ADJUSTMENT IAW JB TASK CARD 190-27-001. ADJUSTED AS REQ`D. REMOVED AND REPLACED AILERON AUTO PILOT BRACKET IAW 22-11-040. ALL CHECK AS NORMAL.