As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE-OFF FROM ANC, GEAR WAS SELECTED UP, LT MAIN WOULD NOT INDICATE UP AND LOCKED. AIRCRAFT RETURNED FOR AN UNEVENTFUL LANDING. DETERMINED LT UPLOCK ACTUATOR WAS BYPASSING FLUID. REPLACED UPLOCK ACTUATOR. SUBSEQUENT GEAR SWING AND FLIGHT CHECK WERE SATISFACTORY.