Ok, here is the deal, I happend accross 4 33x12.50x15 BFG AT/KO's at a used tire place, tires had prob about 95% of the tread left... all four for $100 needless to say I got them, have them mounted now, but on my stock rims, now my question is, will the width of these tires cause a problem being on rims this narrow or should it work ok? I'm not worried about rubbing or them fitting on the truck, I'm running 4.5" of total lift and own a sawzall :D What I am worried about is a tire falling off a rim or something stupid like that happening... any ideas? suggestions? (other then just running out and buying new rims for no reason, my budget is in neg numbers after swap I'm doing :) )

Just do the chalk test and make sure the pressure is right. And don't air down too low offroad. You should be ok.