Wouldn't a big hit simply bent the joints above the attachment to the front crossmember & pivot the remaining of the bumper (whatever is above the pivot point) into the front body, resulting in strong bumper crunshing into the body & radiator?
That bugged me too when I did my bumper. Unfortunately, there is no way out of it on the yota's....the front cross member just hangs low.....so you're always gonna end up in with that rotation problem. The flip side to that issue is that a truck frame really isn't all THAT strong to begin with. And a "good hit" to a really ridged bumper will bend the frame.
I think I mentioned the story early of my buddy's S-10 with a big *ss box steel bumper on it. He got hit head on at like 20 mph. His bumper wrecked the other car, visually the bumper looked completely un-damaged, but his frame was bent. The accident wracked his frame.
Knowing that, I built my bumper to be pretty ridged, but I intentionally put bends in the tubes that support the main part of the bumper, so it would bend at those points if I got hit good. I can lift my truck up with a high lift in the front (not on the sides near or past the headlights though). But I'm hoping that if I do hit anything hard upfront the bumper bends and rotates into the radiator, like you mentioned. I'd much rather replace sheet metal and radiators than a frame.
The only real downside I can see is that you really shouldn't mount a winch to the bumper. That should go directly off the frame at the same level as the cross member. Which puts a winch kind of low on the yota's (at least in my opinion).
At any rate....ANY bumper is an upgrade from the stock 1/16" stamped steel things. Those aren't protecting anything. Even the mounts on mine were 1/16" stamped steel. I could bend the thing with my hands.
