I have a 1999 Dodge Ram 1500 V6 that has been squeaking for a long time now, slowly getting louder and more obnoxious. The belt and belt tensioner were bad so I replaced them, but the squeak was still there. Then I replaced the tensioner pulley, followed by the alternator, but it still squeaks. If the belt is removed and the engine run, there is no squeak. Its very hard to localize where it is coming from - as best I could tell it was coming from the tensioner or the alternator (they are next to each other), but with both of them replaced and nothing else nearby I am at a loss. Looking through some other discussion boards seems like another common problem is the fan clutch. Mine actually went bad 4-5 years ago so I replaced it back then, but this squeak is different than what it was doing back then, so I’m hesitant to replace that again.