The contact owns a 2016 Ford Expedition. The contact stated that while driving approximately 35 MPH and hauling a trailer attached to the tow hitch, the trailer suddenly detached from the vehicle. The trailer hitch had fractured due to extensive rust. The dealer was contacted and informed about the failure. The vehicle was not diagnosed or repaired. The manufacturer was informed of the failure and opened a case. The manufacturer referred the contact to the NHTSA Hotline to file a complaint. The failure mileage was approximately 129,000.