What was found
THE AIRCRAFT WAS GROUNDED. APPROX 2HRS + 45 MINS INTO FLIGHT LEFT HYDRAULIC QUANTITY BEGAN TO DECREASE RAPIDLY. THE FLIGHT DECLARED AN EMERGENCY AND DIVERTED TO DFW WITHOUT FURTHER INCIDENT. NOTICED HYDRAULIC LEAK UNDER NR 1 ENGINE AFTER AIRCRAFT ARRIVAL AT GATE. MAINTENANCE REPLACED LEFT ENG HYD PUMP PER MM 29-11-11. REPLACED SYS A PRESSURE, RETURN, AND LT ENG CASE DRAIN FILTERS. INSPECTED AND NO DEBRIS NOTED. LEAK CKS OK.