As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE LT HYDRAULIC SYSTEM QUANTITY AND PRESSURE WERE LOST WHILE AT CRUISE. APPROPRIATE CHECKLIST ITEMS WERE ACCOMPLISHED AND THE AIRCRAFT WAS RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND AFT FUSELAGE HYDRAULIC FILTER UNION LEAKING AT LT PRESSURE BULKHEAD. THE UNION PACKING WAS REMOVED AND REPLACED. LEAK AND PRESSURE CHECKS WERE GOOD.