How much space do you leave between the custom rear bumper and 4Runner body to allow for body movement or flexing? I'm working on plans that would use a 4x2 rectangular tube, capped off at the ends, with tubing running out from the ends, then turning 90 degrees towards the rear wheels. I don't have any pics, but one of the DeMello rear bumpers is the closests example I could find (the last 2):
http://www.demello-offroad.com/rear_bumper.html

I'm not sure how much space to leave so the body doesn't rub against the tube when rocking back and forth offroad.

 

I'm wondering the same thing, and from what I've heard so far 1" should be enough at any point on the rear bumper to the body.

Chris

 

I recently found a discussion nested in a thread that mentioned 1" - 1.25" to allow for the flexing. My rear bumper plans are all drawn up and will have it built and mounted in a couple of weeks. I'll post pics once it's done.