Mine had the worst squeak. It did not matter what the heck I did I could NOT get rid of it. Just about drove me nuts.
If the vehicle even moved at all it was loud. Real loud, so loud the stereo would not drown it out.
Tore everything apart. Was just sure it was this, no, sure it was that, no. Almost bought a body mounted tire carrier (Not that I dont need one) was just sure that I had damaged my tailgate inside.
Funny thing was that when stopped I could shake and jump up down all I wanted and could not recreate the noise. Bumps did not seem to make a difference.
Long story short it turned out to be the fuel filler lines that run alongside the left rear fender. I used small rubber pads and a few zip ties and it completely solved this dreaded squeak.
I am telling you, I checked everything at least ten times. My wife was about sick of me before I found the problem. It was making me phsyco :gaah:
Grab your fuel filler cap and shake it. If like my 2013 it is real loose and you can hear the squeak right away when you do. Not the cap itself but the line set connected up to the body at the fill area.
See the body moves and the fuel tank is mounted to the frame. Jeep:doh:
Good luck finding your problem. Be sure to update us with what you found the problem to be.