Cab Mount Chop - Food for thought?

That's my point. Because the CMC is not obvious it would be extremely difficult to tell it had been done when purchasing the vehicle. My point is it's a modified safety part. Even if it's stronger than original all the lawyer would need to do is put doubt in the jury an it's all over.

Except the steel is high strength. As HiPSI pointed out it it's not possible to repair high strength steel to the original strength. Toyota does not allow for repairing the high strength steel parts of the truck.

 

No. Frames are much stronger, cabs, they look the same but are totally different metals too.

 

I stated my opinion on what I believed the behavior of a welded 3/16" plate of CRS to a formed cut based on the face removal of steel in the corner of the cab mount. Not as a matter of fact, but rather what I believe the behavior will be, so please don't contextualize wht you said parenthetically as me stating it as fact. You would be wrong. Also, not the mount itself and how the tire/wheel would be, in my opinion, incapable of penetrating the cab. 1) due to size. 2) due to the speed of impact in the video and the energy dissipation of the rubber tire contacting a larger area as it's compressed/flattened against the wheel well, while the alloy wheel is sheering off the bolts, deforming, and moving under the cab in such a short amount of time. You can see from the video itself the tire/wheel moving under the cab as it bounces into the wheel well after the wheel is sheered off. 3) you still have a firewall that the tire/wheel would have to penetrate through before entering the cab.

it is a downward deflection and the only thing I could see possibly encroaching into the cab would be a brake rotor, but i would put that in the rare column.

We are talking about removing a corner of steel, not the entire back inner wheel well. Also, that mount is on the underside of the cab surrounding by plate (stock or welded into place). Force concentration on that spot by the wheel/tire could possibly sheer the cab mount itself, but it would still have to go through the stock formed wall or through the welded CMC which to my understanding based on the BAMF plates is something like 6"x6"x3/16"

Also, let's look at this in context. People who get CMC's are doing it in order to get larger tires. if that's the case, they are most likely getting a lift of at least 2" (an assumption), so with that, the cab itself is lifted, which in all likelihood of a head-on collision would position the tire/wheel combination in an even better spot to not encroach into the cab in a head-on collision. Again, just my opinion. Thanks for sharing yours.

 

Sure, but that is high force concentration into a small space where the steel has little energy and little reaction time to dissipate all of that energy on that point of contact. In a collision like in the video there is all sorts of energy dissipation going on in a lot of places. Designed as intended.

 

Actually, your question brings up a point i don't think I've seen yet. Does a CMC void the vehicle warranty?

 

Ummm, I think you are mistaken in thinking the firewall or the wheel well in these trucks are some sort of solid steel armour plate. These trucks are designed to be lightweight, with strength only where needed.

In this post, there are, near the beginning, some very interesting links regarding structures such as cab mounts, and the fact the Tacoma cab mount is clearly longer than it needs be to support the cab, is pointed out as well.

Honestly, I think you’ve dug yourself a hole and are looking to justify a very weak position. The reason the tire (clearly to me at least) in the video does not crush the occupants legs is that it hits the cab mount.

Please, no one here is stating that we are experts, but you are really coming across as close minded on an issue that is multi-faceted. Maybe if you didn’t have mouths for eyes, this would be more clear. I dunno.

All the best to you.

 

More reading for when you’re on the shitter:

http://news.crrtraining.com/working-with-toyotas-high-strength-steel-and-ultra-high-strength-steel/

https://www.repairerdrivennews.com/...ning-will-weaken-higher-strength-auto-steels/

https://www.repairerdrivennews.com/...or-company-in-north-america-first-on-a-truck/

vv Not a diagram of the frame, but this cab structure gives a clear idea of just how complex these vehicles are getting in terms of crash-worthiness and lightweight construction.

 

Why would I be mistaken about something I never said or implied. I never said or implied that the firewall or the wheel wells were some sort of solid steel armor plating. That's your projection of what you think I meant. I didn't. I've dug no hole since I was simply giving my opinion. If you don't like that opinion, that's fine and it's really no skin off my nose either way. I'm just not sure why you're calling me close-minded or attacking me... with an avatar I use? Seems petty.

I hope you got the answers you were looking for either way.

 

Honestly it's amazing that anything can be repaired on these any more... Maybe that's why we keep seeing the threads about trucks being totaled with damage that appears to be fairly minor.

Of course the flip side of that is it seems that these trucks do an amazing job of protecting the passengers which is far more important than the ability to repair the truck.

 

One could always add a square tube to the frame:

 

Well that doesn't look at all like "O shit we just failed the small overlap front crash test. Now what do we do?"

Way to go Chrysler

 

Serious question OP, if you are so concerned about the cab mount chop why do you need it?lifting it alters all these characteristics. Bumpers alter this. Sliders alter this.

If your so concerned about the tire coming through the floorboard or crushing their legs then sliders would prevent this. What you should be more concerned with is the diameter of the bolt holding it to the mount. I've seen plenty of those fail in accidents

 

Did you read the rest of the offerings for those Ram Variants and what they are stuffing them with? Amazing just as it is stock. The interior alone was drool-worthy and I'm not even a Dodge guy.

 

You guys do remember the 05’s with bad frames right? Where you’d bring your truck in for a recall and Toyota would cut the front 4’ of your frame off and reweld a new section back on and wouldn’t tell the customer.

Last thing I would worry about is that cab mount. Also, many dealers are doing CMC’s to fit 285’s on brand new trucks.

 

I do remember the Motor Mount Sections collapsing, always thought they just added bracing, had no idea they went that drastic.

 

I don’t understand how sliders affect a front corner impact, please explain.

 

Well, I'm not twelve years old anymore so just because someone does something does not mean it's cool or right.
A few posts above a guy claims that rock sliders will deflect the wheel of the cab mount won't. Seriously, no calculations, no nothing.
05 frames are totally different material than 2016+. You can't do that anymore.
Sure, dealers cut the cab mount. They assume that liability and that's fine. They are not Toyota and that does not make it right.

In the end, you must make your own decision based on what you know. This thread has a lot of good information and also some terrible information. I didn't need this thread as I've known for years the UHSS high boron content. I pay attention to the crash testing. I do it to keep learning.
If you decide to chop after reading this thread that's great. The best thing is you at least read this thread and got a bit of science behind the cab mount instead of blindly following someone else. Good luck and enjoy the truck.

 

Tire would hit the slider not allowing it to come through the floorboard like you think.