I was getting a new squeak recently that I thought was coming from the back seat. It turned out to be the screws that hold the picnic tables to the back of the front seats. I noticed two screws lying on the carpet in the drivers side rear. The screws had backed all the way out and the other two were very loose. The other tray also had four loose screws. I was glad the holes in the back of the seats were not stripped out. After tightening everything up, no more squeaks.

If you have the tables on your car you may want to check the eight screws.