As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER DEPARTURE LOST HYDRAULIC SYSTEM A PRESSURE. CONTINUED TO ORD AND WAS TOWED TO THE GATE. *S/D* REPLACED HYD FLAP DRIVE MOTOR AND NR 1 AND NR 2 ENGINE DRIVEN HYDRAULIC PUMPS PRECAUTIONARY. ALSO, REPLACED CASE DRAIN AND PRESSURE FILTERS PER MAINTENANCE MANUAL. LEAK CHECK OK.