on 31's you shouldn't rub but you may have trouble doing some good offroading. I have 4" BS but I got a 2" BB also, I am not sure of the offset but they stick out a bit but I like it and a little wider stance is not a bad thing. If you want to be sure mount a tire on the wheel(they should not have any problem doing this if you are buying them at a tire shop) put on the front and turn the wheels both directions all the way to see if they hit or how close they come.
2006 Jeep Wrangler TJ SE 2.4L(4 angry squirrels under the hood) 3.25" RC lift, 33x12.50R15 Firestone Destination AT's
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