What was found
DURING CRUISE, ENROUTE, THE NR1 ENGINE DRIVEN HYDRAULIC PUMP (A) SYSTEM LOW PRESSURE LIGHT ILLUMINATED. FIVE MINUTES LATER, THE NR 2 ENGINE DRIVEN HYDRAULIC PUMP (B) SYSTEM LOW PRESSURE LIGHT ILLUMINATED. HYDRAULIC SYSTEM QUANTITY WAS OK AND HYDRAULIC SYSTEM PRESSURE REMAINED AT 3,000 PSI WIGHT ELECTRIC PUMPS. FLIGHT RETURNED TO FIELD AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. COULD NOT DUPLICATE PROBLEM. ALL HYDRAULIC SYSTEMS OPERATE NORMAL. REMOVED AND REPLACED THE P5-8 OVERHEAD HYDRAULIC PANEL AS PRECAUTIONARY. OPS CHECK GOOD.