Finally Had this rattle coming from behind front seats that sounded like rear seat latches or rear seat belt buckles hitting the doors while not using. Would hear this rattle when driving over slightly bumpy or rough roads and driving very slow. Or on an uneven surface while truck was flexing. Was not the following things. Not the Jack behind the seat Not the rear sliding window Not the tail gate Not The Retrax rolltop cover Not the rear doors latches or panels Not the gas tank skid plate under the truck Nothing loose under truck Not the rear shocks. Not the sliding sunroof. It was the rear glass panel of the sunroof that does not move. Found it by geting in the back seat while wife was driving and holding a little upward pressure near the back of it. Fixed it by loosening four of the six screws that hold it in place. Just a little. Then slighty repositioning the panel up and down a tiny bit but making sure it was put back exactly where it was. Also, I lubbed the rubber seal with some of that special lube. I actually think it was the lube alone that fixed it. Completely quiet now Completely happy.