What happens when you roll a 4x Innovations Roll Cage?
For quite a while I’ve been working on setting up some roll cage testing. I have finally managed to make it happen. To start out I had a 1986 4 Runner that used to be my daily driver. Being in the rust belt, it needed a lot of help, more help that what it had become worth. I decided that it was time to get rid of it, and prove out some engineering simulations, and have a little fun at the same time.
’86 4 Runner
Engine, transmission/transfer, driveshafts are all installed and intact.
4x Innovations Passenger Length Internal Roll Cage built with DOM tubing - 4RIC-D.
Harness Bar Upgrade
Dash Bar Upgrade
I left the frame tie in kit off to get a good baseline of just what a cab floor can handle.
I created a time lapse video of the install. As you can see install is simple as long as you know how to weld. The key to this level of simplicity is all tubes come prenotched, ready to weld (dash bar and harness bars do not come notched).
The test assumptions:
The truck is not a fully loaded wheeling rig. It is short a few hundred lbs of tires, suspension, seats, fluids, and fuel tank.
These are not all worst case rollovers. Everything should be considered for reference only.
The rolls were not performed on rocks; however there were several rocks in the path. Additionally rolls 4 and 5 were performed on frozen ground.
On with the goods.
The first roll is just to show what the truck and cage do in a basic typical roll over. The hill has about a 2 foot tall drop at the top leading to a smooth transition to flat. On the first roll the truck went over on the passenger side and rolled 1.75 times.
Damage report: The windshield cracked, but did not shatter, and the windshield frame is still straight. From studying the crack patterns and photos the windshield actually landed on a rock and it was not the opening itself deforming. The passenger side wing on the rear bumper also took a very hard hit which bent it inward some.
Roll # 2 same spot, driver side first. The trucked rolled 1.5 times
Damage report: Nothing new other than standard sheet metal damage.
Roll #3 We moved to a nice steep, tall hill. Once we got the truck to what we thought would be a good position we sent it on down. However this roll ended up actually being softer than the first two. The truck rolled once down the shallower portion of the hill right at the top of the steep portion of the hill the truck ended getting swung around up facing straight down hill and slid to the bottom.
Damage report: Nothing new.
Roll #4 We moved to a taller hill with a 4 ft vertical drop off at the top to a steep embankment. For this roll we pushed the truck off the top from the rear. This caused the truck to flip end over end at the bottom of the ravine.
Damage Report: In this case again there was no discernible damage to the roll cage. The result ended up being more interesting as to what happened to the front bumper mount more than the roll cage. The bumper itself did not bend at all, rather the lower factory weld nuts pulled through the frame cross member and the entire cross member deformed. This is a perfect example of why the front of the frame should be reinforced using a frame reinforcement kit.
For the 5th roll test we pushed the truck sideways off of the top of the same hill as #4. This roll was an amazing display of gravity and the strength of the 4x Innovations roll cage! The truck completed 3 full rolls. The side hit on the 3rd roll came after a nearly half of a revolution with the truck air born.
Damage Report: After this incredibly violent roll the passenger compartment is still intact thanks entirely to the great strength of the DOM tubing on the 4x Innovations Internal Roll Cage. The front A pillars of the cage shifted to the driver’s side by about 4 inches, the B pillar about 2 inches, and the C pillars shifted 1 inch. An important thing to note is that the cage still has only shifted to the side, it has not shrunk in height, nor has it pushed backward toward the seats even after this abusive series of tests. Obviously the cage is not straight anymore, but it did not collapse. After all that this truck and cage has been put through I am very proud to be able to say that.
Final notes: There are several very important notes that all considering installing a roll cage must remember; Roll cages MUST be installed by a professional welder. The welds holding the cage tubing together is just as important as the tubing itself. Also the cage tested here is the DOM cage. DOM tubing carries a significant strength improvement, meaning the tubing will absorb larger forces before permanently bending. This should be taken into consideration when purchasing a roll cage.