I have a '97 Ram 1500 which the water pump went out on. When I replaced the pump I changed out the belt, which was thrown when the pump died. Since then there has been a pronounced screech coming from beneath the hood. I found that by spraying a lubricant on the spindle for the idler pulley AND the tensioner pulley, the noise would stop. So logically, I replaced both pulleys and the problem stopped temporarily. Then within a few days the problem reoccurred. Again, spraying lubricant stops the noise for a minute or two, but I still have to hit both pulleys. What is causing both pulleys to go bad? The water pump is installed correctly and the belt is properly installed and aligned. I could understand maybe getting a bad new pulley, stuff happens, but both of them bad? Unlikely.
Could the noise be comming from some other belt driven component? when you spray your lubricant (which I dont feel is good for your belt) it gets on the belt and the belt is not affected by the real noise maker (it slips rather than transfering energy)
I had the tensioner go bad. Not the pulley, the whole thing. On a 1989 Ram Charger.