Honestly, if you're not going to off road that much, just keep it stock. These things are remarkably capable out of the box. But if you do want to go bigger, I personally wouldn't go bigger than 285/75 without a lift and regearing. But there's some guys that say the 315/75s are fine on the stock gears. Expect lots of rubbing off road if you don't lift and go with the 315s.