As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT, VIBRATION OCCURRED IN A TURN THAT COULD BE FELT BY OUR FEET AND SEEMED TO ORIGINATE IN FRONT OF US. WX RADAR STARTED TO ACT ERRATICALLY AND VIBRATION STOPPED WHEN WE TURNED OFF RADAR. GROUNDED - YES. REMOVED & REPLACED RADAR PEDESTAL DRIVE. REF B737-900 AMM 34-43-11-000-802 & 34-43-11-400-802.