I have 35" Nitto Trail grapplers on my rig. (96 7.3 F250 w/4" lift). The tread on the inside of the front passenger tire is wearing a little unevenly. One lug is high, one lug is low, the next is high, the next low, and so on. It appears to be just the inside portion of the tire that's like this, the rest seems to be wearing evenly. Any idea what's causing it? They haven't been rotated in awhile, maybe 2 or 3 oil changes. I'm just trying to figure out if reballancing and rotating is all I need to do, or if there's potentially a suspension component that's bad, or the wrong air pressure (I'm running the psi that the Nitto rep said to run), or alignment is out (I just had it aligned, twice), or something else. Tia.