They might rub a bit on the lower suspension arm up front. However, that's an easy fix but not really neccessary to mess with unless the noise embarrases you. Just remove the steering stops and place a thin washer in front of that welded nut. This will fix the rubbing but your turning radius with be compromised a bit.
On the rear it might rub on the fenders a little with a lot of weight in the back. My 00 XJ had 255/70/16 and they rubbed when a couple of people sat in the back seat. Of course, those tires were approx 30X10.5...way too wide. However, I think some guys have mentioned that a 30x9.5 sometimes rubs a bit in the back on the newer XJ's because of the design change. On my old 88 XJ, 30x9.5 tires never rubbed on the rear fenders.