My car in question is my 1997 Ford Thunderbird 4.6L v8. Back Story: For most of last year I was technically living in two places at the same time while I was working at PowerColor. I would stay with my aunt during the week and then go to my mother in law's to be with my daughter and fiancee for the weekend. Story behind that, but I'm not getting into that here. Anyways, the drive from PowerColor to my mother in laws was 2hrs / 110 miles long. Over the summer, the serpentine belt decided to snap while driving to my mother in law's house and I had to pull over and left it overnight at a rest area until the following day when I replaced the belt. I thought everything was fine after replacing the belt, but I immediately noticed that there was a "chirping" noise once I installed the new belt which was not noticeable before with the old belt. Troubleshooting already done Removed the belt and reinstalled it thinking that I missed a groove / tooth when I installed the belt the first time I have sprayed the crap out of idler and tensioner pulleys with WD-40 thinking it would be a bad pulley What is most likely the cause of the chirping noise? The tensioner or idler pulley? An improperly installed belt even though I've already removed it and put it back on? A miss-aligned pulley system? Something else? The videos below are ones I came across. The first video is one I came across yesterday and based on what it said, I hadn't even thought about it being misaligned pulleys! That makes me wonder if that could be the problem. But, I'm not sure why it would have happened with the new belt and not with the old belt.