You have it backwards.

The air bags deploy when the cockpit slows down too fast, like in a collision...

The bumpers are not what really absorb the impact, they primarily distribute it.

The exceptions are stock bumpers with little shock absorbers built into them, but, many people don't realize that this is NOT to protect the occupants....this is to make a flimsy bumper able to pass the 2.5 or 5 mph bumper tests, as needed.

The forces in a crash severe enough to require airbag deployment to save you, are so in excess of what these little bumper dampers deal with, as to render them meaningless.

The truck as a whole, if the crash is severe enough to slow the passenger compartment too much, will crumple at its pre-designated crumple zones.

Adding a strong bumper does not make the truck slow faster, it tends to make the OTHER object crumple and absorb the impact instead....AND, it tends to DISTRIBUTE the force of the impact across the entire face of the bumper, rather than allow it to focus upon the point of impact.

For example, all of the aftermarket bumpers attach to the frame horns, the same way the stock bumper does.....so, that's the limiting factor for all of them...

...if the crash is severe enough to crumple the frame horns, the accordion-like crumple designed into the trucks will work as normal.

If you look at a typical crash, say against a tree, or the corner of an incoming car, etc...the truck has to do ALL of its impact absorption on the middle, or side point of impact....

...and if you look at accidents that involve this, say a head on square into a tree... the truck is always pushed in at the point of impact...like the tree pushed the engine down, crumples the hood, etc...and makes a path visible through the middle of the truck....as in the two headlight ends are behind the tree, but the tree is against the windshield, etc....

...meaning that the tree impact involved a section down the middle alone, and the part that absorbed the impact was not helped by the parts to the sides.

Same with a corner to corner collision...the most common type....one corner does all the crumpling, and the middle and other side are bypassed....unable to absorb any of the impact.

The more of the truck's structure that can absorb the impact, the slower the rate of slowing will be, as each part of the structure absorbs more and more of the incoming impact...like a catcher's mitt being drawn back on impact to soften the hit of that fast ball, etc.

If you have a strong front end, with a steel after market bumper...

1. It takes a lot of force to do any damage at all in the first place, because the OTHER object is forced to do the absorbing.

2. If you are going to hit something that will not give (A deer gives when Shrocked, most other cars give when Shrocked, a bridge abutment or a big tree, etc...probably would not, etc...)....and you are hitting hard enough that the frame horns are going to crumple anyway...

....the ENTIRE front end of the truck will be working to save your ass...all three crush zones will be slowing your rate, not just one.

So, sure, you will possibly total the truck either way if you ram a big tree or another car at 60 mph...the difference is you might live.

3. As the sensors for the bags are in the cabin...if you need them to go off, they do, as normal, period.

They are just less likely to NEED to go off, as you are less likely to need them to save you from injury.

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All of the after market bumpers will help in this regard...even if they themselves are sacrificed in the process.

The difference between a Shrock and an ARB for example would be -

The ARB has thin 10 gauge Sheet Metal, vs the Shrock's 3/16" Steel Plate for the faces.

The Shrock uses one continuous 3/8" thick Steel Plate from the recovery points at the front of the bumper, welded through the bumper face, braced by 1/4" Steel Plate boxing and triangulation, running all the way to the frame horns.

The ARB's 10 ga sheet metal with 3/16" bracing is a lot less substantial, and it is not tied directly and continuously back to the frame horns the way the Shrock is, so it will crumple more, and protect less....

...but, even the ARB distributes the impact across the face of the bumper, and I've seen the results of them taking head on impacts, and protecting the truck from being totalled, or even damaged in some cases...they themselves just tend to take more damage, but, they do work, and it does take a lot of impact to hurt the primary structure.

They weigh as much as the Shrocks mostly because they are a lot larger overall, and more thin metal can weigh as much as less thick metal, etc.

So - ARB and Shrock are not the only bumpers, but as the two mentioned, the above is a comparison.

TJM, KMA, and Calmini for example make sturdy bumpers too.



ALL of them work better than a Brush Guard...even if they can also be damaged by a severe enough accident...it just takes A LOT to do any damage.



Again..the aftermarket BUMPERS do run from their fronts to the frame horns...so impacts tend to be straight at the frame horn lines...at your maximum strength point.....

Brush Guards cannot run straight back to the horns...all the plastic and stock bumper is in the way....so they need to have a mount that loops way down, under all that stuff, and then back up, to reach the horns...making a giant lever arm...

Its this giant lever arm that makes the brush guards ineffective protection...its just too much force applied by the involved leverage to resist, and they fold back, etc.

So, sure you CAN fold back a steel bumper if the hit is substantial enough, but it takes WAY more to do it than for a Guard.