A pull plow attaches to the rear hitch, which is attached to the frame. A front plow attaches to the plow mount which attaches to the frame. Not a whole lot of difference.
Actually, there is a huge difference. A front-mounted conventional plow is very hard on the front end components. That's why you can't put a plow on the front of an F-150 without voiding your warranty. It has nothing to do with the frame itself.
A pull plow doesn't put any stress on the front end components, as it is carried by the frame and rear suspension.
And if you didn't know, our 4Runners have fully boxed frames, just like those Super Duty pick-ups you mentioned earlier. Our frames are very robust and adding a simple pull plow is no problem at all. I've actually used a pull plow on my 4Runner and it worked perfectly. In fact, you can use a pull plow on much lighter duty vehicles than a 4Runner.