If your top hose goes through the belt, making it impossible to change the belt without removing the hose, then definitely change the upper hose to one off a dual alternator truck. The hose goes under the alternator and around the outside of the belt. Otherwise, see how soft they are getting. I had to replace my lower on the side of the interstate in central Texas once because it got too soft and the clamps wouldn't hold anymore. And do yourself a favor and replace those tension clamps with the worm-drive hose clamps.