Need Help Belt squeaking

I just put a new belt on about 3 months ago because some coolant got on it and it was squeeling really bad. well now its doing it again. originally it would happen until the truck was warmed up and driven for a half hour and between 1500 and 2000 rpms. Now it does it when its cold and only does it for the first 15 minutes or so. I drove it to the dealership (its still under warranty) the other day and about 10 miles before i got there it stopped doing it. they tried for 2 hours to get it to make the squeek and found nothing. They tried the tension pulley, water pumpm and a/c. But every morning it still squeeks. Belt dressing doesnt really work either. i think i can hear it coming from the driver side near the alternator. Does anyone know whats cuasing this?

 

Does belt dressing stop it even temporarily? If not it might be something else. It's rare that dressing on a good belt, properly tensioned will squeal. In fact I've never seen that. I assume you cleaned all the coolant off of everything right? Ethylene Glycol is a lubricant. If you didn't clean everything very well you may have contaminated the new belt.

 

Did you buy a new belt from the dealership or an auto parts store? I've bought belts from auto parts stores before and they never fit right. The NAPA belt for my previous truck was slightly long (maybe 1/4 to 1/2 inch when compared to the old belt it replaced) and squeaked like crazy so I took it back and got one from the dealership. It was shorter than the NAPA one and solved the squeaking problem.

Also, humidity in the morning when the engine is cold can make belts squeak.

 

Are you sure it's not the tensioner you hear? When those bearings start to go they will squeal.

 

The truck is fairly new, an 09 with 28k on it. So I wonder why the bearings if that's what is would be going so soon. But belt dressing does work, if only for about fifteen minutes or so.

 

Yea that is too new for the tensioner to crap out. My '06 has a little over 70K on it and still has the factory belt. I've never had any trouble with it. You might try a new belt. I wish I could offer more suggestions.

 

Take some steel wool or a green scruby and clean all your pulleys really well. Also as stated, it may just be the belt is not fitting properly.

 

Thanks I'll try that

 

Inspect the belt for signs of wear/damage on the ends. If no damage, lightly spray water on the belt while it's squeking. If the squeak goes away, the belt is bad. If it stays, one of the pulleys is going. This assumes you don't have a slight misalignment of a pulley.
If the belt is good: With the engine off, one at a time, oil the bearings of a pulley, start the engine, repeat until the noise changes. The one that stops squeaking with oil needs replaced asap.
There is a possibility that the fan clutch is dying. Look for excessive rust on the shaft and play in the bearing. Replace if sloppy.

 

Park it overnight at the dealership, start it up in the morning for them.