As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DESCENT INTO JNB, FLIGHT 6212, FELT VIBRATION AND COULD NOT ISOLATE IT. POST FLIGHT INSPECTION FOUND NR 4 ENGINE TAILCONE LOOSE AND BRACKETS BROKEN, ALSO FOUND TURBINE EXHAUST CASE CRACKED. REPLACED NR 4 ENGINE AND PERFORMED ENGINE RUN PER MM CH 71-00-00.