I am looking at a 97 f2504x4, and the owner has two year old cooper discoverer at3s on it with fine looking tread wear. I am curious though because he runs sand bags in the bed even in summer because he says the rear end handles loose when it gets wet out. It's got a 351 and was used to plow early in it's life. Now sitting just over 160k, is this a tire issue or a worn out suspension thing, or just a big truck thing? Compared to a car or compact truck it kind if feels floaty when cornering or Changing lanes.