So, the guy at Off Road Canada says I have to have a minimum of a 3" lift if I'm going to use BFG's at 33x12.5x15 on new 15x8 4"off-set wheels and not have the tires touch the frame or body.

Would you agree?

I thought they would just fit without a lift.

 

even at that lift and tire size you might have contact issues if you drive aggressive offroad daily street driving you should be ok.I am assuming that you are talking about a TJ since you never said what you have i have a 2.5 inch susp lift 1inch coil spacer and a 2 inch body lift i have 15x8 wheels with 3.25 inch back space tires rub on control arms behind the front tire and the frame in front of the front tire