The contact owns a 2016 GMC Yukon Denali. The contact stated that while driving 40 MPH, the contact was notified by another driver that the rear taillights were inoperable. No warning light was illuminated. Neither a dealer nor an independent mechanic was contacted, and the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and informed the contact that there was no recall on the VIN related to the failure. The manufacturer was notified of the failure and opened a case and referred the contact to the NHTSA Hotline to report the failure. The approximate failure mileage was 104,000.