What was found
AFTER T/O, RECEIVED LT LG MAIN GEAR UNSAFE INDICATION ON PRIMARY AND SECONDARY GEAR RETRACTION GEAR INDICATION. RAN QRH, GEAR PRIMARY OR SECONDARY LIGHTS ILLUMINATED W/ GEAR HANDLE UP CHECKLIST. LT MAIN GEAR UNSAFE INDICATION REMAINED ILLUMINATED. DUMPED APPROX 8500 LBS OF FUEL. DIVERTED TO KLAX AFTER GEAR SELECTED DOWN FOR LANDING, RECEIVED 3 GREEN DOWN & LOCKED INDICATIONS W/ NO UNSAFE. EMERGENCY DECLARED. CHECKED LANDING GEAR DOOR TARGETS PER AMM 32-10-00-5. ADJUSTED AS NEEDED. REMOVED AND REPLACED LT MAIN GEAR RETRACT CYLINDER PER AMM 32-31-01-4. OPS CHECK GOOD REMOVED AND REPLACED LT MLG DOOR ACTUATOR PER AMM 32-34-01-2. OPS CHECK AND LEAK CHECKS GOOD.