As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMBOUT, AIRCRAFT EXPERIENCED EXTREME VIBRATION AND ASSOCIATED LOW RUMBLING NOISE IN THE AREA OF L3 AND FORWARD LOWER GALLEY NOISE. DUMPED FUEL AND RETURNED TO MIA. INVESTIGATION REVEALED THAT LEFT HAND GROUND CONNECTION AC PANEL DOOR WAS MISSING. DOOR REPLACED. CAUSE OF LOSS OF DOOR WAS DUE TO UNSECURED LOCKS ON DOOR.