What was found
AIRCRAFT ROLLED RIGHT AS AIRSPEED INCREASED USED EXCESSIVE AILERON TRIM, ATTEMPTED TO COMPENSATE WITH RUDDER TRIM. AT CRUISE THERE WAS (FL360) SHUDDERING AT .78 SLOWED TO .75 AND SHUDDERING WAS SIGNIFICANTLY LESS. USED AILERON TRIM W/ A/P OFF BUT DID NOT CORRECT SITUATION. GROUNDED - YES. DIVERSION - PERFORMED LEFT AND RIGHT AILERON INSPECTION REF 27-11 TASK 802. ITEM A THRU D. NO DEFECTS NOTED. REMOVED AND REPLACED UPPER AILERON PCU (SYS B) REF AMM 27-11-71. REMOVED & REPLACED LOWER AILERON PCU (SYS A) REF AMM 27-11-71. ACCOMPLISHED BLEED, LEAK CHK, ADJUSTMENT, OPERATIONAL, AND TRAVEL TESTS FOR BOTH PCUS REF SAME AMM. ALL TESTS PASSED. ACCOMPLISHED RUDDER TRIM SYSTEM TEST REF AMM 27-21-00, NO DEFECTS NOTED.