Cage to Frame Stiffening chassis up

[NOTPRETTY]

Went to 1 tons, and 40's about 3-4 years ago. I ran it for about 1-2 years and then began a frame off rebuild which is still in progress. I noticed the chassis flexes way more with 1 tons and 40's. More than I want. Especially in the rocs. I fight the chassis flex so much that at times it is hard to get the rig to steer where I want it to go. It flexs as I turn and bac up and then when I start forward and steer in the other direction is flexs again pushing me bac to the same spot. Not sure if you understand that... Anyway.

Has anyone tried to connect the roll cage to the frame from nose to tail to add strength and stiffness...With the goal to turn the chassis and rollcage into one structural unit?

What did you do and what results did you get?

What would you do different?

I am going to add tube from the down bars at the dash forward to the nose of the rig and down to the frame near the front body mount. You can see the tube in the last picture below. I'm considering connecting at several places...sliders to frame...B pillar to frame...and debating wether to weld direct to the frame or issolate the connections with 3/8" thic rubber slabs at the frame. I fear ride quality on the road if I go too far. I also fear stiffening the frame might create an imblanced of stiffness and it might push more flex elsewhere and I'll be chasing future problems. Might be best to do nothing. I'm really interested in feedbac from others that have done this.

Thoughts?

[NOTPRETTY]

Re: Cage to Frame Stiffening chassis up

Hmm. Has anyone connected their cage to their frame?

[NorcalKD]

Re: Cage to Frame Stiffening chassis up

Hmm. Has anyone connected their cage to their frame?

My cage is tied into my frame. I came off my rocksliders with a plate, sandwiched my floorboard with the baseplate of my cage, and tied them together with grade 8 bolts.

Last thing I want in a rollover is my cage punch through my swisscheese floorboard.

[TBS-POPS]

Re: Cage to Frame Stiffening chassis up

From the standpoint of what your trying to do to solve your frame flex problem,NO. To do frame tie-ins to keep roll cage from separating from vehicle during a catastrophic rollover, Yes. Bronco frames are not the most rigidly engineered things to begin with anyways and to stiffen things up with tying the cage to it would prob result in enough cross bracing in it that there would be no room for passengers or drivetrain!!! Your better off ditching the weak bronco stock frame and building a tube chassis of sorts with a bronco body on it.

[welndmn]

Re: Cage to Frame Stiffening chassis up

It seems strange to feel frame flex in an EB, if it's flexing and your feeling it, it would be by the trac bar mount, I would add another cross memeber.
My cage is on my frame and sliders, mainly for safety.

[NOTPRETTY]

Re: Cage to Frame Stiffening chassis up

It seems strange to feel frame flex in an EB, if it's flexing and your feeling it, it would be by the trac bar mount, I would add another cross memeber.
My cage is on my frame and sliders, mainly for safety.

So you have your frame connected/welded directly to your cage and sliders...yes? It seems to me that would eliminate frame flex. I have a ladder...you have a frame with a attached box/cage to lock it all together...completely different deal. But keep reading...

The bronco stock frame is nothing more than a ladder with two steps and the third is only two bolts holding the transfer case/trans crossmember in place in the middle. Yeah...bumpers help a bit at the ends, but not much. Beyond that you have body mounts that connect to it and they should create a ridgid frame tub combo. You'd think the body mounts would strength the frame and they do, but its not as strong as you think. In my case it is like my tub is floating on top of the frame...no matter how tight I secure it. I've cut out the rockers and welded a 2x6 in place which left the body flexing like mad. I have a two inch body lift. My cage is not tied at all to my frame and the cage stops entirely at the firewall.

I thought...this frame has to be cracked some where or something is failed.... I've checked all my frame for cracks or bad welds I even looked for hairline cracks...its not cracked. I think its a combination of a tub that has been wheeled hard since 1989 and is metal fatigued. Combine that with body mounts that have loosened up on me several times...compounding the issue...add cutting off the rockers and add in 1 tons and 39's stretching things further than ever before and you have my rig...tub and frame flexing like a rubber band as it goes. One thing for sure... If keep wheeling it this way the frame will eventually crack...tub too.

If you watch my tub...say at the door gaps as I drive up on a huge rock 4-5 foot tall...on the passenger front tire, the entire body flexes and twists from nose to tail. The gaps change significantly as the rig crawls along. 3/4" - 1" gap change is visable. I thought this was not normal until I started watching other rigs with 37" plus tires and no cage points tied in or tube work added past the firewall. In fact its not normal, but many rigs flex way more than their owners realize...especially when people have hacked off their rockers like I have.

Many people don't see it until someone points it out. They complain their doors aren't working...but don't put the two together.

I want to increase safety...for sure. And I want reduce the flex overall, but not make it so stiff that driving on the highway makes every bump and hole come up through the chassis into my hands and arse. I think adding a cross-member might be wise...stiffen the frame first. I am adding cage to the nose of the rig which will help a ton. I'm going to add frame connections where the cage connects behind and infront of the driver/passenger...for safety. What is that...the B and A pillars? Anyway, If that is not enough, I'll connect at the rear and front.

[GREMLIN]

Re: Cage to Frame Stiffening chassis up

we use to use spring bushing on the end of the cages on old school offroad trucks tied to the frame rails. made bridge out of the cage.