Are Bed Stiffeners Required w/ A Crossbar Bed Rack System

I understand the benefits of bed stiffeners and their purpose. But in my mind, crossbars bolted to the bedrail would do the same thing? The fixed connection should hold the bed in place and would limit the amount of flex from the top of the bed. Is my theory flawed or does someone with a similar setup have any bed flex issues?

 

I would say yes the same ish. Same with a shell. Extra protection when keeping it square over long periods of time

 

Having a shell is one of the reasons many of us install bed stiffeners since the extra weight can make the bed flex and rip in the weakest points near the tailgate

 

A shell creates a pivot point at the connection between the bed and shell. With a fiberglass shell and weak bed, it's allowed to move and cause the bed to flex. Where as a steel beam bolted to the bedrail would be a lot stronger of a connection. Again, these are my assumptions. Not sure if I am correct here.

 

I would say that unless you've got a beam crossing way back on the bed rail you're still going to be leaving that section vulnerable. But that's also just a guess

 

I agree with that. It brings me to my initial question though, what additional benefit would bed stiffeners add to my setup if there is still multiple points for the bed to flex. The $150 for piece of mind argument doesn't make a lot of sense if we're on the right track of how a bed takes stress of additional weight.

 

I would say no. Any weight at the rail caps and above is going to add load in the corners and no amount of reasonable bracing at that level is going to help. Even absolutely rigid connections (imagine just a metal plate spanning the bed rails and well connected) is adding load.

Putting an RTT, cap, or such up there would have me installing stiffeners with them. Cheap insurance.

The main thing is that a lot of folks find no spreading, but I didn't want to take the risk.

It might sound silly, but after I installed the stiffeners and only having a rollup tonneau at the time, the rear felt stiffer going over familiar bumps. I acknowledge that could have just been in my head as it was a pretty subtle difference.

 

Takes maybe $20 in materials to make some.

 

Very true, but you can't discount the creation, skills, or tooling that is used in the process. Fairly, I believe they are worth $100.

 

Fair.

Have a buddy make them!

 

Can someone point me to some evidence as to why bed stiffeners are necessary in practice vs theory? I’ve never known anyone’s bed to get tweaked. Thx!

 

Has anyone actually measured the flex with a shell installed? How bad does it really get? How much better do stiffeners make it?

 

@Das it mang

Got pics of the bowing of your bed before and after bed stiffeners?

 

Maybe I am misunderstanding the load but doesn't weight on the bedrails cause the bed walls to bow outwards, and the crack occurs at the connection point between walls and bed? If the walls are supported at the top, how do the walls bow out causing a crack at the bottom? Bed stiffeners stop the bed from bowing out, so should braces at the very top holding the bed in place.

Both solutions are meant to stop the lateral load.

 

If your cross bars are not attached near the mid height of the bed sides, they are not limiting the flex moment as much as they could. They are helping, but not as much as a bed brace which counteracts the flex at the hinge point. Your cross bars form a box without diagonal bracing, the bed stiffeners serve as the diagonal bracing (in an abbreviated fashion).

 

Before n after. Only couple months with the shell but I'm rough on my truck

 

It's side to side loads.

 

True, but unfortunately folks that work metal as a hobby are not very common anymore.

 

Your theory in the op is accurate, but your implementation is what needs improvement. Those bolted rails at the L joint will do nothing, so with that roof top tent weight real bed stiffeners would be good security. Now if you welded that L joint, AND added a triangular stiffener to the joint (that started at the bed rail), assuming you have used decent wall box section, then there would be no need for bed stiffeners.

 

You are assuming that the weight pushes both sides out. It could be that the weight is pushing both bed sides to the left or to the right at the same time.