Full 6 Point Roll Cage

One of the better improvements in the evolution of the Jeep has been the addition of door bars on the factory roll cage (Jeep refers to this as a "Sport Bar" because "roll" has such bad connotations associated with it!) This design has some shortcomings because the door bars attach directly to the windshield frame, relying on the frame and hinges to support the weight of the vehicle during a roll over. I've seen many YJ's with this configuration crush the windshield frame during a roll. Moreover the rear of the roll cage consists of two rectangular "ears" than extend from the center hoop to the rear corners. I felt that this was insufficient protection for rear passengers (i.e. my two daughters) because those ears could easily fold inwards during a rollover. Thus I designed a rollcage that retained the stock cage and the mounting points for the door frames and soundbar, retained the ability for the windshield to be folded down, and allowed me to use the stock softtop and my Bestop Bikini top. The fabrication work was done by Ron Griffis at Innovative Chassis in Gainesville Florida. He constructs custom tubular dragster frames and has considerable experience in mandrel bending and cage fabrication. He recommended thick walled 1.5" diameter chromoly tubing as opposed to the stock thin walled steel because it would be least obstructive and could be passed behind the dashboard without much difficulty. Anything that could burn (i.e. carpet, soundbar, safety belts, seats, softtop, rollcage padding) was removed before fabrication started.

First, all the tapered slip joints in the stock roll cage were circumfrentially welded after the old connecting cross bolts were removed. A front crossbar was welded connecting the forward portion of the doorbars (more about this later). Dual centerbars were mandrel bent at one end and welded 12 inches apart between the front and center crossbars. The bend is necessary because the center hoop is slightly taller than the doorbars, and a straight connecting bar would be too close to my head! The center gap could be used to mount a CB or radio - I chose to mount a console for the rear air suspension valves and gauges.

An important point is deciding how far back to mount the front crossbar. I chose to weld the bar at a point 1" behind the lower edge of the extended sunvisor - just behind the forward mounting hole for the door frame. This position allows me to keep the stock sunvisors and provides sufficient clearance for the soft top latches.

Contrary to popular belief a downtube can be passed through the dash corners without disassembling the dash. The windshield needs to be folded down and the weatherstripping at each corner trimmed. After trial fitting we found that a 1.5" hole saw cut just back of the forward edge of the dash creates a path for the 1.5" tubing to pass behind the speakers and HVAC ducts without any modifications. The bars were then mandrel bent to compliment the rake of the windshield frame, and welded to the stock doorbars in front of the forward doorframe mounting hole. The corresponding bracket on the doorframe had to be trimmed with a Dremel to acommodate the downbar. This design preserves the original brackets connecting the doorbars to the windshield - buttressing the windshield frame and preventing any vibrations at high speeds. It also preserves the ability to fold down the windshield if you ever want that "bugs-in-your-teeth" driving exhiliration!

The bottom end of each tube is welded onto a 5X7" steel plate that is welded to the tub. Unlike the YJs and CJs it is very difficult to tie this point to the frame or to support it beneath with an extended body mount because the TJ tub as a two-layered floor at the perimeter. I felt that the large mounting plate would be sufficient to spread the forces out. A fellow TJ owner in my club with an identical cage in his Jeep rolled his ride last spring at Moab without any structural damage to the cage or tub (his fenders, grill, and hood bit it hard, though!)

A rear crossbar was added at apex of each rear "ear" to prevent the hoops from collapsing inwards. This also serves as a handy mounting location for the GPS antenna and does not interfere with the soft top operation. It does slightly limit rear head room, so I padded it liberally for protection.

Much of the original rollcage padding had to be cut and modified. I used closed cell foam hot water pipe insulation for padding, and covered it with Rapz bar wrap from ProComp.

The total cost came to about $500.00, and all the conveniences of the original cage have been preserved. The final construct is light, stiff, and very strong.