Maybe it's whole purpose is to keep the dirt out?....
That's sort of what I mean. If it were necessary and they haven't been doing it up until now....then they dropped the ball. If it really isn't necessary, (as in there are plenty of tried-and-true truck chassis designs out there that see
much heavier duty use that light trucks ever will, and yet they aren't boxed in), then saying this is a feature and marketing it as advantageous is just, well....marketing.
I'm not just pointing a finger at GM here, there are a couple of other light truck manufacturers that also advertise their recently-adopted "fully boxed-in" chassis designs. I'm just saying that it's certainly not as if mankind only recently stumbled upon concepts like strength and rigidity, or the properties of metal stampings in different shapes or forms.
Of course it could be suggested that light trucks are moving towards boxing-in rather than making the chassis beams beefier like a medium or heavy-duty truck chassis has in order to save weight/improve fuel economy, etc.
BUT.....then what they're
really saying, is that they're making a "spindly-er" tube-style chassis, in order to achieve the same strength as a channel-style chassis. Which, once again....makes it not really a "heavy-duty" feature.
