As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEAR DISAGREE WARNING AFTER TAKEOFF DURING GEAR RETRACTION. LEVELED AT SAFE ALT TO RUN QRH. JUST AFTER WE STARTED QRH GEAR WENT UP ON ITS OWN. COMPLETED QRH AND CONTINUED. GEAR OPERATED NORMALLY DURING EXTENSION. (FLT#3134) CLOSED PERFORMED FULL STRUT SERVICE IAW AMM. PASSED FUNCTIONAL FLIGHT.