kingbaby

I've got an 05 fx4 with the 5.4 v8.. It's been making this really loud screeching noise and my buddy said it sounds like serpentine belts.. Whatever it is there's definitely two of them and I wasn't aware there were two serpentine belts.. It'll make the noise randomly and then once I'm almost to a stop one will make like a thud and it'll feel like something catching and then the other one will do it right after.. It seems like belts but I don't really know.. Any thoughts?