I used 2x6 on mine, but if I were doing it again I would go with 2x3. 2x6 just adds more weight (and cost) without adding any real benefit. In order to add any real side protection, you need to have an outer tube that extends further from the body.
My original idea was that it would extend out far enough to function as a step, but 2x6 isn't wide enough to to that very well unless you extend it further outward. If you do that, you really need to make the supports strong enough to prevent them from contacting the pinch weld and possibly causing damage.
If you keep the tube under the pinch weld, it can flex upward without damaging the seam, as the load will be distributed along the entire length of the seam, reducing the chance for damage. Only downside is that it will slightly reduce your ground clearance, However, it still will be as high or higher than the bottom of the frame rail.
My original idea was that it would extend out far enough to function as a step, but 2x6 isn't wide enough to to that very well unless you extend it further outward. If you do that, you really need to make the supports strong enough to prevent them from contacting the pinch weld and possibly causing damage.
If you keep the tube under the pinch weld, it can flex upward without damaging the seam, as the load will be distributed along the entire length of the seam, reducing the chance for damage. Only downside is that it will slightly reduce your ground clearance, However, it still will be as high or higher than the bottom of the frame rail.
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