Squealing serpentine belt?

C

cottondoc

new to site
Yesterday, out of the blue, my serpentine belt started chirping or squealing nonstop. I’ve only driven probably 100 miles or so around town and two lane roads since it started, but it is getting progressively worse. I sprayed the belt with WD-40(all I had available at the time)with the truck idling and the squeal would stop for 1-2 seconds until the WD-40 had worn off. I tried to check all the pulleys for play or signs of failure at the alternator, water pump, and power steering pump but I could not see anything obvious. There is no water leaking from the water pump and the truck runs normal and cool. The alternator is charging normally and the power steering seems to work normally. Nothing changes the squeal but engine rpm changes the speed. Any ideas on what it is or how to diagnose it? I had three water pumps go out, one on my 2007.5, one on my 2014, and one on my 1995, so that was my first thought. But all of them leaked water. They did not make the belt squeal. Could it just be the belt worn out? The truck is my 2006 5.9, 48re with 148,000 miles. Thanks for any help or info.


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Could be. I recently went through a similar ordeal with my 12V. I pulled the water pump and it had a tight spot that would chirp when you spun it, replaced it. Still had the squeal. Pulled the alternator and sent it to have bearings put in it. Was told the bearings were bad but the stator was also bad and he gave me a new alternator (he’s a good friend). Still had the squeal. Fan hub was definitely good and the compressor pulley was good. All that was left was the tensioner, original with 550K on it. It felt similar to the water pump so I replaced it. Still had the squeal. I didn’t want to remove the belt because it looked ok and I have to remove my crank sensor “conversion” to get it off. Sprayed some belt dressing on it and the squeal went away, so I put a new Gates HD green belt on it. Not a peep from it since.
 
Changing a belt with everything in place with a Fluidamper on a 6.7 pretty much sucks due to the clearance is all I have to add.
 
I used to throw water pumps away from core engines, but 3 years ago, in the summer, I had 2 guys in 1 week kill water pumps on the side of the road and I had one go out on me last year.
Now I don't toss water pumps that seem like they might be usable. :D
I save decent belts, too.

I'm wary of belt noises.
For me, if one makes any kind of noise, I'm all over it trying to figure out why it's making noises.
You'd be surprised what a weak, worn belt tensioner can do to belts and all of the different, ugly noises a bad one can cause.

Mark.
 
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Mark Nixon said:
I used to throw water pumps away from core engines, but 3 years ago, in the summer, I had 2 guys in 1 week kill water pumps on the side of the road and I had one go out on me last year.
Now I don't toss water pumps that seem like they might be usable. :D
I save decent belts, too.

I'm wary of belt noises.
For me, if one makes any kind of noise, I'm all over it trying to figure out why it's making noises.
You'd be surprised what a weak, worn belt tensioner can do to belts and all of the different, ugly noises a bad one can cause.

Mark.
Click to expand...

Had an alternator go out on me on Nov 14th..... that sucker made horrible grinding noises intermittently til it just gave the ghost.
 
I'm amazed at the abuse the alternators on these trucks do take, especially on high horsepower engines.
They are typically 5 or 6 to 1 overdriven, get punished not only by torque, but the oscillating loads from belt "surge" (there's a better term), then on top of that, there's the loads, amperage wise.

It's no wonder you heard it coming apart. :hehe:

Water pumps make horrible noises, too!
Especially when the steel impellers chew up the block cavity, which is rare, because usually the bearings are gone and the belt comes off by then.

Mark.
 
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RacinDuallie said:
Lawsuit pending??:poke:

There had to be pain and suffering through your trumatic experience.........
:hehe:
Click to expand...

:hehe:

The damages weren't worth pursuing!

Funny part is my truck actually has a full bumper-bumper warranty on it right now.

They paid for the Alternator.
 
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agreeing with mark. from what ive seen its the tensioner 90% of the time. i keep a spare one in the truck box along with a water pump. in my experience the water pump leaks before it squeaks, but no 2 failures are the same i guess
 
Update on mine:
After putting the Gates HD on, two months later it started squealing again. Long story short, I meticulously cleaned every groove on every pulley and went to a standard black Gates belt. So far, so good.
 
autoferret said:
fan belts are cheap. 1 second the Gate HD green belts rock!
Click to expand...

X2 Just swap the belt with a Gates Green belt. While you've got the belt off, take a look at the pulleys while they're out of tension. Swap the water pump if you want, since the serp belt is actually a PITA on the 6.7. $.02
 
My 2003 would start chirping when a new belt was 10-15000 miles old. I kept a can of comet powder under the back seat. When it started chirping, I'd dump a little on the crank pulley. No chirp.
 
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