What was found
REPETITIVE PITCH VIBRATION AND FLUTTER ON CLIMBOUT AND AGAIN AT CRUISE AND REPEATED MULTIPLE TIMES DURING DIVERT AND AUTOPILOT WOULD NOT ENGAGE. PERFORMED GVI OF ALL PCU'S AND ELEVATORS. FOUND LH CENTER PCU LEAKING AND SQUEAKING WHILE BEING ACTUATED, ALSO FOUND LH ELEVATOR TO HAVE EXCESSIVE PLAY WHILE HYD SYS ON, SUSPECT FAULTY CENTER PCU & BUSHINGS IAW CRJ550 AMM 27-33-01. R/R LH CENTER ELEVATOR PCU IAW CRJ 550 AMM 27-33-01 OPS CHECK GOOD.