As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - FLT 1904 - EN ROUTE DFW-SJU, SHORTLY AFTER TAKEOFF DETECTED LOUD SQUEAL AT R4 DOOR. LOUD SQUEAL INCREASE WITH AIRCRAFT PRESSURE. RETURNED DFW AND LANDED WITHOUT INCIDENT. TRIMMED INTERIOR SEAL AROUND FRAME AT R4 DOOR. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)