My truck is a 2000 5-speed 24-valve, and if start coming down through the gears as I let the clutch out (down shifting) I here a squeal. I can make the truck make that sound over and over by just coming down through the gears and kinda dropping the clutch. ( I don't drop it normally I was just trying to figure out where the sound was coming from) It doesn't do it as I shift up and let the clutch out, only during down shifting. Is this a clutch that is going out? I thought it may be the u-joints It also seems to rattle at speeds up to 35 to 40 mph. after that say highway speeds its smooth as silk.