As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, SELECTED GEAR UP AND GOT A GEAR DISAGREE MESSAGE. THE LEFT AND RIGHT MAIN GEAR DID NOT LOCK UP. WE SELECTED GEAR DOWN AND RETURNED TO THE AIRPORT. REMOVED AND REPLACED MLG PRIORITY VALVE IAW MM 32-32-15. PERFORMED SYSTEM TEST OF THE LANDING GEAR PRIORITY VALVE IAW MM 32-30-00, OPS AND LEAKS CHECKS GOOD.