One problem related to gas tank strap has been reported for the 1999 Chevrolet Silverado 1500. The most recently reported issues are listed below.
My son was driving my 1999 Chevrolet silverado at 55 -60 mph and the gas tank straps failed (rusted completely through) and the gas tank fell out onto the highway. Before he could determine what had fallen off the vehicle, there was a hole worn in the tank due to being dragged on the asphalt. It spilled a full tank of gas on the highway. The truck had to be towed on a flatbed truck. We had to replace the gas tank straps, fuel pump and gas tank. There were no injuries but the fire dept. And police had to be called as a precautionary measure before we could load it onto the flatbed tow truck .