ARB Bullbar 2005+ Tacoma

[Overland Hadley]

your right the new ones work off a G-force sensor cause my ARB doesn't have any crush zones. I've bump tree and rocks pretty hard and the bumper hasn't moved an inch.

So then would the airbags work any better with an ARB than a Shrockworks?

 

[cruiseroutfit]

Here are two questions.

It is my understanding that the second gen. air bags do not deploy from a crush sensor, but from a impact sensor (like a g-force sensor). Is this true? If it is, then why does the ARB bumper need to crush?

And if the ARB does crush, then would that not make it fold under a minimal impact. Kind of like, why put on a big bumper if it will crush easily. Although I suppose that it would fold easily only in one direction, that of a head on impact.

Any ideas on these thoughts?

The bumper is designed to decelerate at a prescribed rate. If it decelerates too slow (ie crushes alot) it might not fire the airbags (or not soon enough). If it decelerates to fast (ie a very rigid bumper that doesn't crush), the airbags might prematurely fire. I would rather replace a bumper than a life. Beyond that, its the testing... I'm sure other bumpers might pass the testing, but until they shell out the $$$, you leave yourself open to the liability accordingly. In this litigous society we live in, its not a comprimise I'm willing to take. Would I sway other from buying a different bumper, absolutely not, there are some killer designs on the market, make it your choice for your reasons

The older Tacomas had the crush cans Wil posted a pic of... I've got some here that I'll grab some pics of to show the "neat" things about them

 

[HMR]

So then would the airbags work any better with an ARB than a Shrockworks?

I've never understood this either. I thought the airbags were triggered by a little ball being displaced at a certain G-force level?

Does the ARB connect to the frame in a different spot than all the other bumpers?

 

[HMR]

The bumper is designed to decelerate at a prescribed rate. If it decelerates too slow (ie crushes alot) it might not fire the airbags (or not soon enough). If it decelerates to fast (ie a very rigid bumper that doesn't crush), the airbags might prematurely fire. I would rather replace a bumper than a life.

Interesting. That means the cheap stock plastic is designed to decelerate at a prescribed rate?

I'm sure other bumpers might pass the testing, but until they shell out the $$$, you leave yourself open to the liability accordingly. In this litigous society we live in, its not a comprimise I'm willing to take.

If true, I think the bigger liability rests with Shrockworks, Demello, Bent-up, etc. If someone was injured in an accident and could prove the bumper affected the airbag deployment that would probably be the end of aftermarket bumper manufacturing.

 

[cruiseroutfit]

Interesting. That means the cheap stock plastic is designed to decelerate at a prescribed rate?

Absolutely! Not a doubt in mind Toyota plans their stock bumpers to "crush" at a set specification, thus deploying the airbags at a certain point of impact. Changing anything with regards to the bumper will to some degree change this relationship, thus why testing a bumper design might not actually have any design changes on the bumper, rather just guarantee it allows the airbags to deploy as designed.

 

[heeltoe989]

I've never understood this either. I thought the airbags were triggered by a little ball being displaced at a certain G-force level?

Does the ARB connect to the frame in a different spot than all the other bumpers?

No it connects at the same point as the stock bumper, but also uses allot of other frame mounting points that the new Tacoma already has. I'm sure a shrockworks and ARB would act very similar in a heavy impact.

I always think of it as, if the airbag is going off my bumper is my least concern.

 

[Overland Hadley]

The bumper is designed to decelerate at a prescribed rate. If it decelerates too slow (ie crushes alot) it might not fire the airbags (or not soon enough). If it decelerates to fast (ie a very rigid bumper that doesn't crush), the airbags might prematurely fire.

Now I understand it!

Thanks for explaining it cruiseroutfit, the way you described it makes sense to me.

I learn something new every day on the ExPo.

 

[Overland Hadley]

The older Tacomas had the crush cans Wil posted a pic of... I've got some here that I'll grab some pics of to show the "neat" things about them

That would be great!

 

[Lost Canadian]

A few things worth mentioning. The new Tacoma's front frame section is dimpled and is designed to crush in a stong impact. If you crawl under the front of the truck and check the front frame rails you'll see what I'm talking about. If you hit something hard enough it wont matter how beefy the front bumper is, the designed weak point will still be the front frame rails.

Also, with the ARB bumpers it's more then meeting airbag standards. The Aussies, build these bumpers to meet certain industry design regs., namely regulation ADR 69/00. Here's a PDF overview.

 

[heeltoe989]

A few things worth mentioning. The new Tacoma's front frame section is dimpled and is designed to crush in a stong impact. If you crawl under the front of the truck and check the front frame rails you'll see what I'm talking about.

Also, with the ARB bumpers it's more then meeting airbag standards. The Aussies, build these bumper to meet certain industry design regs., namely regulation ADR 69/00. Here's a PDF overview.

Very cool information.

 

[cruiseroutfit]

That would be great!

Here you go:

You can see by the construction how they have a "crush section", the neat thing isn't as much the design, but the fact that all 3 sides are manufactured out of one peice. As an engineer I am constantly amazed my neat manufacturing practices, this one surely includes that.

 

[cruiseroutfit]

How does it deal with winch loads, afterall these bumpers need to handle winching too, right?

Well, they use two of these straps per side, as you can see they are designed to buckle when compressed (front end collision), yet withstand the load of a winchpull, its easy enough to calculate the amount of force they can take under tension, thus not stretching the "crush" elements. Neato I keep a couple of them around to use as visual aides, and we have used them at ARB tech seminars in the past too, very useful tool to "show" instead of "tell"

 

[daverami]

How does it deal with winch loads, afterall these bumpers need to handle winching too, right?

Well, they use two of these straps per side, as you can see they are designed to buckle when compressed (front end collision), yet withstand the load of a winchpull, its easy enough to calculate the amount of force they can take under tension, thus not stretching the "crush" elements. Neato I keep a couple of them around to use as visual aides, and we have used them at ARB tech seminars in the past too, very useful tool to "show" instead of "tell"

A lot of engineering in this product. Very informative. A lot different than getting some plate steel and welding it up!

 

[Dave Bennett]

A lot of engineering in this product. Very informative. A lot different than getting some plate steel and welding it up!

Thats exactly why I bought an ARB instead of something custom