Hi there, I’m reaching out because I’m really desperate for some help right now. First of all, I know very little about vehicles, but this will be my third Jeep TJ, it is a 2000 Wrangler SE, four-cylinder. It has about 150,000 miles on it. I bought it about 5 years ago and have had to do very minimal work to it, the person I purchased it from seems to have kept it well maintained. I get on-time oil changes and have my mechanic look over everything whenever it's in the shop. Overall runs very well, but within the last month, I’ve been experiencing a very erratic, scary noise that seemingly comes out of nowhere that occurs whenever I am in a forward motion, whether the clutch is depressed or not, usually anywhere from second-fourth gear, rolling forward with either foot off gas or stepping on the gas, it is a very loud humming whirring vibration noise, almost like a binding/grinding noise. To me it seems like a transmission issue. But I cannot get it to do it on-call, when my mechanic has it to look at. He's driven it around with me in it and it didn't do it both times. It’s completely maddening. I don’t really feel safe driving it. I really don’t know what to do, I am at a point of desperation with this because I need to figure out what my next move will be. I don’t have a lot of money, and I work 30 miles from home. Been limping by with this problem for the last month, but when it happens it is so scary to me that I really don’t want to let it go any longer but my mechanic says without hearing it himself, there’s not a ton he can do. I finally captured it on video today. It’s louder in person then it comes across in this video. Can anyone help? Video link on Youtube posted below. Thanks in advance.