While driving on the highway at approximately 65mph my sunroof spontaneously exploded. It was as loud as a gunshot and glass rained down into the cab as well as exploded upward and outward raining down behind my truck while driving. This startled me and all passengers. There were no vehicles ahead of us or in the oncoming lanes on the other side of the separated highway. No foreign debris was found in the truck and there was no other damage anywhere other than the obvious glass lying everywhere. I previously complained to the dealership during routine service that the sunroof made a rattling sound during light bumps. The routine service was completed and I was given the response of our techs couldnt reproduce the sound(s) so we cant help with that today. They assured me that I could leave the truck and they would look into it when they could but that Id have to leave the truck in the lot and not be given a loaner vehicle.