One problem related to tailgate hinge has been reported for the 2002 GMC C1500. The most recently reported issues are listed below.
I sat on my tail gate and the tail gate fell down. When I looked I had one broke cable and the other side the bolt was missing. I bought two cables from advance auto replaced one side but I could not get the bolt back in the other side. I was planning to take the truck to the dealer the following weekend for the recall but the gate fell off the truck and I did not know it had fell off and I dragged it down a dirt road for about half mile or more. I tried to get GMC to replace the tail gate but they just wanted to replace the cable saying that the cable did not cause the tail gate to fall off and the damage was not due to the cables. I feel that the cable problem caused the tail gate to fall off.