Belt chirp/squeal

[jmb1124]

Howdy all. Got an '05 FX4 automatic with a recurring belt chirp/squeal that is making me park the truck due to noise. Usually silent when cold, then slowly gets worse as things warm up over a drive. I've loaded the parts cannon and everything seems to help for a short while, then it always comes back. Here's what I've done:

• ~100mi after buying the truck, squeak started, and a new Gates belt worked for 5,000 miles, then it returned
• Cleaned some pulleys, worked for another ~100mi, then returned
• Installed a Gates kit with tensioner, belt, and idler pulley. Worked for ~1,000 miles, then returned.
• Since then, the following "fixes" have worked for a max of a few drives:
  • Cleaned all pulleys with brass brush and solvent
  • New Dorman harmonic balancer
  • New alternator
  • New Motorcraft belt
  • New Dayco idler pulley
  • Reman power steering pump (old shaft seal was leaking, thought it was contaminating the belt)

Took it to a shop, they said it was the fan clutch. I removed the fan assembly and it still squeaked, so $80 diag fee wasted.
Some more details:

• Spraying water instantly quiets the noise, and holding a wet rag to the smooth side works as well
• All pulleys look straight with very little wobble if any
• There is a valve cover leak that I'm going to tackle, but I don't think it reaches the belt
• Does not noticeably change with A/C on/off, turning the wheel, or loading the electrical
• Seems worse at idle. Could just be road/engine noise masking it during accel

I'm about to gamble on a new fan clutch, water pump, and pulley just because. With that done, the only thing left is the A/C pulley/clutch, but nothing is making me suspect it other than process of elimination.
At a loss on this one, any ideas?

 

[Li'l Work Truck]

One of your pulleys might be dragging a bit. You're saying you're going through belts real quick? It might be your tensioner pulley, if it's the back side of the belt getting wet that fixes the issue...