Let me start by saying I read a majority of the threads on this board about how to stop a squeaky belt, and I have tried most of them, to no avail. I will explain how everything started, what we did, and I am hoping somebody can chime in on something I missed.

It all started with a leaking water pump. I replaced it, and that is when the belt started to squeak, it never squeaked before that. It was a cheap Dayco belt on there, but it was in good shape with no cracking. After it started to squeak, I pulled off the belt and washed it in soap and water, and also sprayed all the pulleys with brake cleaner to remove any coolant residue. I put the belt back on, and it still squeaked. I replaced my idler pulley and also my belt tensioner pulley, and it still squeaked. I went and bought a new Dayco belt, it still squeaked. I tried belt dressing, spray lubricant, and even soap, and it still squeaked. I cleaned everything off the belt and pulleys again, still squeaked. I swapped the belt tensioner out of another blazer, still squeaked. I looked at all my pulleys and they looked glazed, so I wire wheeled all of them, it still squeaked. I figured it started with the new water pump, so it was probably causing the issue. I was lucky enough to warranty it out and install the second water pump, it still squeaked. I bought a Gator/Goodyear belt and installed it, it still squeaked. I crawled all over trying to figure out where we thought it was coming from and it appears to sound like it is coming from the crank pulley. I watched the pulley and it was running out of round a bit, so I thought it might be the harmonic balancer. I bought a new Delco pulley and a balancer and installed them. It stopped squeaking for 2 days, and has now started again. I am at a loss as to what the issue could be. My last option would be replacing the fan pulley, clutch, or fan in hopes of finding an imbalance, even though they all seem to be fine.

Any suggestions guys? Any help would be appreciated. Thanks.

 

turn up the stereo
sorry ,couldnt resist

 

Maybe its the altenator

 

Get a mechanics stethoscope and start listening to each of the componets until you find it.

 

take the belt off and turn slowly and listen
rear alternator bearings were always an issue on older GM alternators
I have seen that bearing dusting out rust because the seals are gone but it still charges
Take a look at the rear of the alternator JIK

 

That is what I have resorted to....but that isn't fixing anything.

 

I took the belt off and spun the pulley by hand on the alternator. No resistance or indication that it is bad. It is less than a year old and from Napa, but anything is possible.

 

Good call. I am pretty sure i have narrowed it down to the crank pulley, I just have no idea what else I can do to make it stop squeaking. I will see if I can find a steth this weekend and give it a listen.

 

Take the belt off, start the truck, and listen, do not do this for long, seriously. not long at all, if it is a pulley problem, the noise will stop with the belt off (not more than a minute tops) once you determine that its a pulley problem, start narrowing it down.

 

A friend of mine had the same problem he ended up going with a more expensive belt, solved his squeak. My new 2000 squeaks also but its the altenator, found it by spraying WD-40 around while it was running.