One problem related to transmission noise has been reported for the 2006 GMC Envoy. The most recently reported issues are listed below.
The contact owns a 2006 GMC Envoy xl. When the contact started the ignition, he heard a loud whining noise coming from the transmission. The failure occurred without warning whenever the vehicle was in operation. The vehicle has not been repaired. The failure mileage was 30,000 and current mileage was 37,000.