So, I shredded a serpentine belt over the weekend on my 01 DII and finally got it replaced today. I got a new belt on, fired up the truck and noticed a faint rattling noise that sounded like a chain running over a metal surface. Other than that, the truck ran fine. I shut it down and looked around the engine compartment and noticed that the new belt was straddling the power steering pump pulley by 1/8-1/4". I took the belt off again so I could look at the pulley alignment between all of the components and it looks like the power steering pump pulley is 1/8-1/4" more forward than the other pulleys/idlers and is out of alignment. I looked at the attachment bolts to the pulley and the pump bracket and it looks like everything is tight. I need some help here as to what would cause this.

 

It sounds like your power steering pump is coming apart. Probably the bearing. The pulley attaches to the pump with 3 bolts, so if the pulley bolts are tight then it sounds like the part that the pulley mounts to is working it's way out of the pump. The pump failing probably caused your belt to come off and if the pulley goes flying off next then you will be replacing your fan and more than likely your radiator. Get a new pump ASAP.

 

Did you replace the pump recently? It's possibly to install that pulley backwards which pushes it forward.

 

I’m having the exact same issue did you figure out what was wrong with it???