is your bypass hose or thermostat housing or timng cover leaking? the fan will blow it all over the belt, and it wont hit the ground, so you may have a leak and not know it

 

there are no leaks on the front of the engine

 

so can you get it squeak when its idling in the driveway?
if so, try to give the center of each pulley a squirt of wd40 to see if you can identify a single pulley. don't get in the fan...

if all pulleys are good, i'd try a new goodyear belt.

 

My 1994 5.2 has a squeek every now and then. My squeek comes from the AC Pulley. A shot or 2 of WD 40 and its goes away. It doesnt come back unless the truck sits for a few months. Not sure if this will help or not. This is my first post.

 

I was told once by a mechanic that if a shot of wd40 stopd the squeek
then its your belt

 

If a shot of wd-40 stops the squeak then it is the pulley that you sprayed causing it.

 

i have the same problem, on my truck it's a leaking water pump. I din't see it at first but by lifting my truck i could see traces of cooling liquid under my engine (white deposit). i'm changing my waterpump this weekend

 

I've had this problem, too. First, try to listen while it's running at idle to see if you can tell which component is making noise. (In my case I couldn't tell.) Next, if you're careful and are willing, take a WD40 can with a extended nozzle and, while the truck is running, spray each component. Alternatively you can turn your truck off, spray a component one by one, then restart your truck after each one. Don't spray the belt (which is easy to do because of the fan, if it's running). Mine ended up being the AC pulley. However, this isn't foolproof--some components have internal bearings which you can't get to with a spray can. You may need a professional opinion.

 

If you have a Harbor Freight around you then you could pick up one of these http://www.harborfreight.com/cpi/cta...emnumber=41966
then poke around to see if you can find the squeak. The moment it starts yank it off the road and start poking, since it starts after it gets hot and then goes away.