As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EXPERIENCED SUDDEN INCREASE IN VIBRATION ON NR 3 ENGINE FROM 1.2 TO 2.4. RETURNED TO MIAMI FOR AN UNEVENTFUL LANDING. LUBED CLAPPERS, CHECKED CHIP DETECTORS ACCOMPLISHED TEST NR 11 VIBRATION SURVEY IAW L1011 FORM 7102B VIBRATION WITHIN LIMITS.