[stockman]

Did you say fall off or fall open? The tailgate is suspended by two steel cables. It takes a manual release to unhook the attachments between the truck and tailgate. First one must open the gate and unhook both cables, position the gate so the left side of the gate can be lifted off its hinge, pull out and then shift right to seperate it from the left side. As you can see four operations are needed to remove the gate. However if both cables rusted through (there was a dealer recall to change them to stainless steel for that reason) and the latch fail open or if one were driving with the gate down and both rusted cables seperated from their connections the gate could be lifted enough to fall off while on the road.

See your Chevrolet dealer for a free cable replacement with stainless steel cables and your insurance company about who should pay for your new tailgate.