Jeep Belt Squeal!

[TapouT]

I have a 1998 Jeep Grand Cherokee with the 5.2 in it. Last week I got in the Jeep to drive it to work and noticed the belt was squealing but wasn't that bad. I got to work and pulled the belt off and the edges were pretty frayed and noticed the idler pulley had some play in it. All the other pulleys felt okay. I pulled the idler pulley off and some of the bearings were actually missing out of the back of it so I went to advanced on lunch and picked up a new Dayco belt and a new idler pulley. I put them on and for two days the Jeep was quiet as could be and now it's back to squealing again. It's a constant squeal but it's not too THAT loud like some cars you hear on the road. It squeals when you start it up and drive it until you shut it off. What could it be? It's more annoying than anything and I'm assuming since this new belt has been squealing I'll have to replace it again...

 

[upnover]

In my experience, two things will make them do that
1. Belt stretched or loose, and slipping over pulleys
2. One of the pulleys (could be any of them) is putting too much drag on the belt.
Belt isn't actually slipping, but the pulley not keeping up with the RPM's