I have decided to run 285 75R 17. can anyone tell me what wheel width and backspacing I need to still keep the tire under the fender yet not have any rubbing issues? I run a 2011 Rubicon.

 

Let me answer by saying we are running a 255/80 which is 33.1x10 with 1.25 inch spacers on stock 17x7.5 Moab wheels that have 6 in back spacing and it is right at the edge of the fender and room to spare before rubbing. The 285/75/17 (33.8x11.2) is going to be our next tire size and will still have no rubbing with the spacers on the stock wheels.

 

I believe that you could fit those 285/75s on a 17x8 wheel with 4.75 BS and be only about 5/8 inch outside of the fenders.

 

so is there anything I can do from a wheel width or backspacing stance to keep the 285 75s under the fender? state law and I dont want to have issues come inspection time.

 

You might mount them on your current wheels and see if there is clearance. Are you currently using stock wheels? If so, and no rubbing, they will tuck under the fenders.