What was found
ON FLIGHT 3771 (DTW - CAK) HAD A GEAR DISAGREE ON APPROACH INTO CAK. BOTH MAIN GEARS DID NOT COME DOWN, CREW RAN QRH AND CYCLED HANDLE GEAR DID NOT FALL THE SECOND TIME. CREW PULLED MANUAL RELEASE HANDLE AND THE GEAR FELL. CREW REPORTED RECEIVING GEAR DISAGREE MSG AT 6 SECONDS. CREW DECLARED AN EMERGENCY. PA COMPLIED WITH. ONLY FOUND NR 3 HYDRAULIC SYSTEM HAD SOME AIR IN SYSTEM. BLEED SYSTEM NO FAULTS FOUND WITH GEAR, OPS CHECK NORMAL. PSEU WASN'T FLAGGING ANYTHING AND THE CONNECTOR ON SELECTOR VALVE WAS SECURE. BLED NR 3 HYDRAULIC SYSTEM IAW AMM 29-10-00.