2011 Cadillac CTS-V

MY 2011 CTS-V REAR DIFFERENTIAL HAS NOW FAILED FOR THE SECOND TIME. FIRST OFF, MY CAR HAS BEEN BABIED AND EXTREMELY WELL TAKEN CARE OF. THE DIFFERENTIAL FIRST FAILED AT APPROXIMATELY 17,500 MILES AND NOW THIS SECOND TIME AT APPROXIMATELY 38,900 MILES. BOTH TIMES THE DIFFERENTIAL HAS STARTED TO MAKE WHINING AND/OR GROWLING NOISES THAT PROGRESSIVELY GET WORSE. MY DEALERSHIP REPLACED THE FIRST ONE AND HAS HAD THE SECOND ONE BACK ORDERED NOW FOR 2 MONTHS (NONE IN INVENTORY & NO ESTIMATED SHIPMENT). THIS IS A WELL REPORTED ISSUE (109 OCCURRENCES FOUND ON LINE) FOR THESE CARS. WHY HAS CADILLAC NOT ISSUED A RECALL AND AFFECTED A FIX? WHAT ARE THE NHTSA INVESTIGATION RESULTS?

MY CTS-V CURRENTLY HAS 56,000 MILES AND VERY WELL CARED FOR. MY PROBLEM STARTED AT 25,XXX MILES WITH A REAR SEAL LEAK, IT WAS REPLACED BY DEALER AND 9 MONTHS LATER STARTED LEAKING AGAIN. AFTER THE 4TH TRIP TO THE DEALER, THEY ARE NOW TELLING ME IT'S THE REAR DIFFERENTIAL THAT IS A 'KNOWN ISSUE' (WITH RECALLS ON THE EARLIER CTS-V'S FOR THE SAME PROBLEMS) THAT NEEDS TO BE REPLACED. THE PROBLEM IS THERE ARE NO REAR DIFFERENTIALS! GM HAS DISCONTINUED THE PART ( MY CAR IS 6 1/2 YEARS OLD AND THEY MADE THIS CAR THROUGH 2015 AND GM SAYS THE PART IS DISCONTINUED! THE DEALERSHIP HAS INFORMED ME THAT THE CARE IS 'UNSAFE' TO DRIVE AND SUGGEST I PICK THE CAR UP ON A FLAT BED TRUCK AND TAKE BACK HOME AND GARAGE IT.