I did some "mild" offroading with the 30's and did have some rubbing. Then I went ahead and put on my 1in lift and tried that offroad. I did not notice any rubbing after that! I was not very aggressive,I basicly, was trying to rotate the 4wd componens enough to protect them. A guy told me to use the 4x4 at least once a year to keep the seals well lubed if I did not go offroad a lot.
1997 Black XJ Sport 4x4, 1" Shackle/coil spacer lift, Ram Brush guard w/ 6in spot lights, Smittybilt Nerf bars, Class III Hidden Hitch, Elliptical Driving Lamps, Prime Wheels#234 15x8.5, 30x9.50r15, BFG AT's, JVC CD player, Alpine V12 Amp, 1-12in RockfordFosgate Subs, 5-1/4 Rockford Fosgate component speakers in doors & sound bar, Euro-spoiler, Pacesetter Cat-Back, Optima Red Top battery, HID Headlamp Conversion, Gabriel Hijacker Air Shocks on rear axle