As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED HYD 3 ELEV ALERT AT 1 14 ENROUTE (FL 350). HYD QTY WAS 4.8 QTY CONTINUED DECREASING UNTIL RECEIVING HYD 3 OFF ALERT. (QTY 2.8) QRH REFERENCED AND CONTACTED MOCC. LOST 3 HYD WHEN EXTENDING GEAR. LANDED AND CLEARED RWY. TOWED TO PARKING. FOUND THREADS ON UNLOCK CYLINDER RESTRICTOR CRACKED. R & R UNLOCK ACTUATOR REF AMM 32-33-02-4, SERVICED NR 3 HYD SYS REF AMM 12-13-02-3. PREMATURE REMOVAL/INSTALLATION.