It doesn't sound like a problem that I've ever heard about anyone experiencing before, so you're probably not going to get much help from anyone who's dealt with it previously. I'd download the FSM and get familiar with how the steering column goes together, then start poking around to see what you can find. My first guess would be that the column attaching bolts have worked themselves loose somehow, but you may have a loose bearing or something like that.

95 Montero SR
3.8 MIVEC, Advance headers, 2 1/2" exhaust, Magnaflow muffler, OME shocks & rear springs, 2" body lift, 3" tank lift, 4.90s, TRE front locker, factory rear locker, Roger Brown Rock Sliderz, 315/75r16 (35") tires, Sport big brakes