What was found
DURING CLIMB AFTER RETRACTING THE LANDING GEAR, RECEIVED A LANDING GEAR DOOR EICAS MESSAGE. PERFORMED COCKPIT OPERATION MANUAL PROCEDURE, RECYCLED THE LANDING GEAR, AND PERFORMED COCKPIT OPERATION MANUAL PROCEDURE AGAIN AND EACH TIME A DIFFERENT LANDING GEAR DOOR WOULD NOT CLOSE. AIRCRAFT DUMPED FUEL AND RETURNED TO DTW AND LANDED WITHOUT INCIDENT. REPLACED THE MAIN LANDING GEAR UPLOCK SEQUENCE VALVE AND RIGHT WING LANDING GEAR ALTERNATE EXTEND ACTUATOR. OPERATIONAL CHECK GOOD.