I thought my hinges were " tight " too. Here's a good test: open the tail gate, so it's 90 degrees from the back of your rig. Grasp it at whatever place is good for you, preferably near the bottom, and try and lift it. If there's any play AT ALL, the hinge bushings are worn. I just took mine apart and redid them after putting up with the rattling and clacking for over a year,
it finally got too bad. It doesn't take much play in them for the door to make a bunch of noise.
First, I secured the door with some straps to one of my shop rafters to take the weight off it. Then I removed one hinge at a time, disassembled it by removing the round clip holding the pin in, and driving the pin our with a punch. After cleaning the parts up, I could feel the play between the pin and the bushing. I could have went to Napa and bought an oversize bushing, but I found some at my local hardware, and replaced the pins with oversized hardened shouldered bolts. It did require a bit of drilling to get the oversized bushings fit to the hinges, and careful pressing of the bushing into the slightly oversized hole. The hinge material is very soft, and will bend if your ham fisted with it ( ask me how I know.) I ended up using a large socket that fits between the hinge sides to keep it from deforming while pressing in the the new bushing. Sorry no photo's of this, but if you get stuck I could take some tomorrow.
You should be able to find oversized bushings at a good hardware store, and the shouldered bolts, well, that may be a bit harder, but I guess regular bolts would work too. Once I did this NO MORE RATTLES or clacking!