As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON APPROACH TO STL, CREW KEPT HEARING LOUD CRACKING/POPPING SOUNDS. THE SOUND WAS COMING FROM LH SIDE NEAR TIRE ASSY.. CREW ASK APPROACH FOR A SLOWER THAN NORMAL APPROACH FOR ISSUE. ATC DECLARED THE EMERGENCY. THROUGH POST FLIGHT INSPECTION FOUND NO ISSUES