As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING LG RETRACTION, HEARD SERIOUS BANG NOISE WITH ASSOCIATED AIRFRAME VIBRATIONS. INSPECTED ALL FOUR LG ASSEMBLIES WITH WHEELS & BRAKES, & ALL FOUR WW WITH NO DISCREPANCIES FOUND. CHECKED INLET & TAIL PIPES OF ALL THREE ENGS WITH NO DISCREPANCIES NOTED. REPLACED BOTH NLG WHEEL ASSEMBLIES AS A PRECAUTION.