Belt Squeak or Pulley?

[Chief Brody]

Here is a video of the noise...I can't hear it well because of the super duty fan...

 

[HankScorpio]

That's a bearing on one of the accessories going bad. Start taking 1 belt at a time off and isolate which one. I just went through this with my work van, replaced the wrong idler before I got it right.

 

[rampage]

Agree. A squeaky belt would be constant where this sounds rotational when it hits a certain spot.

 

[Chief Brody]

I don't know why I can isolate it with a stethoscope but I cant....I even put some tubing in my ear and got close to each one...couldn't make it out which one.
It is worse with AC turned on...but it also went away briefly with belt dressing

 

[Chief Brody]

All the accessories feel equally "rough" too...one doesn't vibrate more than the other...I guess removing the belts is the only way

 

[HankScorpio]

I tried to spray a bit of lube into different bearings to isolate the squeak. I was 100% positive it was the upper idler. I was wrong, it was a different idler for AC. Total pain to figure out where the squeak was really coming from. Belts are probably your best bet.

 

[diesel4me]

Belt dressing may silence a squeaky belt temporarily,but after that it makes the belt worse often..
Spraying WD-40 on the belt may silence it for awhile,long enough to determine if that is making the noise or not..belts can make the same noise as a failing bearing in the water pump or idlers,it isn't always easy to isolate the noise this way,taking the belt(s) off is a sure fire way to tell..

 

[Chief Brody]

I might as well replace the belts as I do this as they are now 10 years old...

I remember that I had a hell of a time getting one of them on and tightened..don't remember which

 

[Fordum]

Don't worry, I'm sure it will come back to you........