Dude...Those are pretty big tires. I'm not the expert that others are on here, but from what I have read, I would not run those tires without the Dana 44 that the Rubi comes with. I don't believe that anyone runs over 33s with the Dana 35. Again...the 'experts' will chime in, but I think you are pushing it. What I will say definitively is to get the 5 speed. IMO the automatic is just not appropriate for a Jeep.