The main portion of your TJ body is connected to the frame via floor support "torque boxes" or body supports which follow the lower outer edge of your jeep body from front to rear. There are 3 frame-to-body attachment points per side which secure your body to the frame via the torque support boxes.
Now for the bad news...The support boxes are notorious for rusting out and turning into brown flakes which can cause all kinds of structural and safety issues.
OUR NEWLY REPRODUCED UNDER FLOOR TORQUE BOXES, BODY SUPPORTS ARE NOW AVAILABLE AS FULL LENGTH UNITS. THE MAIN STRUCTURE IS PRODUCED IN 16 GAUGE STEEL THE INNER SUPPORTS ARE MADE IN 12 GAUGE STEEL AS WAS THE ORIGINAL. ALL APPLICABLE NUTS FOR SEATS, ROLL BAR AND BODY MOUNTS ARE PRE-ATTACHED. OUR PRODUCT IS OF EXCEPTIONAL QUALITY AND MADE IN THE USA.