Have you heard of a BMC before? AKA Body Mount Chop. It is pretty much just the process of cutting back slightly (or not so slightly) the metal for the body mount directly behind the wheels.

When putting on bigger tires they will generally rub this area and the ways to fix it include, chop it, chop it and cap off with new metal, relocate it altogether (what I opted for), or in addition to any of those, aftermarket UCAs such as SPC that allow you to shift the tire forward in the wheel arch away from the mudflap/body mount area. See this video to show how you can also use the LCA in conjunction to push the wheel away.

https://youtu.be/f2YhnldfI50

Click on this one below to see what it is, and some photos show wheels rubbing against it and where people make their cuts at.

4th gen body mount - Google Search