In case you are curious why Toyota used a front cab mount that is so big...

And in the way of big tires... check out how it deflects the tire in a crash and keeps it from crushing the driver footwell (and the driver's legs.)

 

Sorry, but this is old news.

I agree with the need and what it does.

 

Amazing that they came up with that design ~ 16 years ago

 

Informative post for sure. We don't often take the time to think about how these mods will affect a vehicle in extreme cases.

 

I posted this video not too long ago. The slow mo is hypnotizing.

 

It may be old news, but it's important.

 

Agreed.

I not 100% in the lane with IIHS coming up with more devious tests that manufacturers tend to react to. Although, I am a fan of the small overlap test and am happy to not CMC.

OTOH, I would bet that no one posts here saying that they will now regret the CMC? I am willing to be wrong though.

 

I did a small CMC and I feel uneasy. But I'm confident in my welds and the majority of the strength I retained.

 

The engineering that goes into vehicles is pretty neat

 

These tests are making cars safer (well in these specific situations at least) but also making them a hell of a lot more expensive.

Off the cuff, I don't think a mild CMC will have a huge effect on crash safety as the larger surface area coming from a steeper angle (assuming the CMC was for a larger tire on a lifted truck) should be less of a threat to crushing the cab mount and the footwell. Plus the force will still be transferred to the backside of the mount, which is unmodified in most cases. But I dunno, not an engineer.

I would not do a full mount relocation on my own truck without some serious thinking about it. But I also am not afraid to drive around in my 1979 Jeep Wagoneer, so I may be being hypocritical

 

A lot of people here would disagree, and profess to know better.

 

Okay. Nevermind.

It is not so much about the strength of your welds. It is a full meal deal about the size, shape and location. The only somewhat reasonable arguement that I have read is that the tire to CMC plate is generally maintained, so there is not a lot of room for the wheel to gain energy.

That said, I'm still a fan of the max amount of metal to absorb the energy and the max moment of inertia (b h^3 / 12).

 

Well the size and shape is maintained. You're just pushing the vertical portion Further back. If anything it's better because there's less of a ramp to push the rim up and over the mount.

 

Any CMC is a CMC, in my mind. The wheel is being used as a sacrificial energy absorber when it initially contacts the CM. Once the damage gets to the stiffer part of the wheel, the CM's shape and strength ejects it away from the footwell.

I'm good with the added cost, though I have never been in a serious accident. I have been rear-ended too many times though. I know from my first experience that the seat design was crap and lead to undiagnosed whiplash (my fault for not going in). Cars that we had later had much better headrests that I could feel during the next collisions.

 

That is one way to rationalize it. It's all good as I'm happy in my decision, and I have no leg to stand on to tell you what to do. Just sharing my opinion.

 

Same! Just talking out loud.

 

Naw I want that 35psi pop!

 

Has it been confirmed that this is the purpose of the cab mount? Or are we just speculating?

 

And here I was thinking it was just because they didn’t want people putting 35’s on their trucks.

 

Yes, that info comes right from Toyota.