you don't have to change your shocks for those, but from personal experience, as soon as you get a 3" block you need a stiffer shock or you will bottom out all the time, then you have to cut the bumpstops out, that's just my opinion......you dont have to but highly recomended......Iowa Bob said:No, only have to replace shocks with lowered leafs.1- 2-3-4" blocks are O K