As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEAR DISAGREE WARNING WHEN EXTENDING GEAR. RAN QRH, MANUALLY EXTEND GEAR. AFTER MANUAL EXTENSION THE LT & RT MAINS DOWN & GREEN. R & R THE MAIN LANDING GEAR SELECTOR VALVE IAW AMM 32-32-10. OPS AND LEAK CHECKED GOOD. BOTH EXTENTION AND RETRACTION SUCCESSFUL.