OK, first of all this is NOT a belt issue. I've been getting a "chirp" that sounds just like a bird every 45 to 60 seconds from the front of the truck. It's a very quick sound, less than a second by far and fairly loud (loud enough to hear it inside the cab with the windows shut and radio on softly). It's not speed related, it's not RPM related. I thought it might be my AC compressor clutch engaging and disengaging but it does it when the AC is off, and turning the AC switch on and off will not cause the noise. I did a search and found nothing in any of the forums about this sound. Any ideas? It's driving be nuts.

Mine does the same thing. Mine is the belt tensioner.

Mine does it, but only when the AC compressor is running. Actually I think it does it when the compressor shuts off.

Crawler,
Mine did the same thing and it turned out to be the belt tensioner. I had it replaced under warranty and now a year later it's doing it again.


JP

Thanks for the info. I'll have to check out the tensioner.

This sounds like mine. The dealer is trying to fix it according to TSB's. They thought it was the belt, then the alternator. Now they are looking at the AC bracket. The odd thing is, my truck is not chirping when cold. I think the dealer is troubleshooting the cold squeal problems. Are your trucks with tensioner problems only chirping when warm?

I have been fighting this on my truck for months. Replaced the
belt, no chirp for 3 weeks, then it comes back. Replaced the
tensioner, the chirp stopped for a month. Replaced the grooved
idler, still chirped. I took off the belt, and cleaned all of the pullies
with a tooth brush and strong soap. Washed the belt in the dishwasher
(when wife was at work). Chirp has been gone for 2 months now.
I figured something got on the belt, and was worked into the pully
grooves. Who knows....? It's ok so far.

Mine chirps but it usually does it at about 60-80 mph... Only when warm, will not do it cold...

Permatex belt dressing in the spray can will cure most chirps and will not collect dirt. It has worked for me for 15 years now. Later! Frank

Mine chirps like you describe only when I run the air conditioning.

As information, my wife's 93 Astro van with the 4.3 V-6 has had a recurring "chirp" that ended up being a bad bearing in the belt tensioner. Even a "better" bearing eventually ended up failing. Am thinking that it might just be a GM design flaw that affects other models.

mine chirps only for a short time and usally only last for about 30 seconds or so



by that time it is usally dead):h

Mine does this mainly when my defrost is on. I was experimenting the other day, and it would quit as long as the fan was not on. Is this a bad thing.

I have a chirp that emits from inside the driver's door.

I also have "The Chirp."


It only occurs when the vent fan is on. The ac doesn't have to be running but it seems to occur more when the ac is on, but it will happen with just the vent.

I have this also and I'm pretty convinced that it is the AC as it cycles on and off. The belt probably chirps as the clutch engages on and off.--K

I have it too, from up above / to the left of the steering column, almost sounds like it is in the door. Happens only when fan is on, A/C on/off doesn't change it. Extremely regular, you can time it, every 45 seconds or so. Now that I think about it, I do seem to hear it a bit more when the truck is warm and I am hauling a trailer... I have not checked if the recirc setting effects it - I took it to my dealer and just had the belt and tensioner replaced and sound is the same, they also cleaned out a mouse nest (no mouse) from the blower housing, it didn't fix it either..Some similar posts with no resolution -

http://www.dieselplace.com/forum/showthread.php?t=16902 (http://www.dieselplace.com/forum/showthread.php?t=16902&highlight=chirp)

http://forum.thedieselpage.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=008250#000000

One guy said it was the water pump, another one was guessing at the recirc air door being pulled open at higher speeds and the door having to close again - It is driving me crazy, I wish I could figure it out.

I have found that for the belt chirp remove the belt, clean the pulleys with brake clean sand them with 180 grit to deglaze them, mainly the smooth ones and it will be gone.I Hope this helps.

My dealer thought I was nuts. Nice to see I have company. I figured it was a random belt related thing. Gonna try the Permatex solution if I can figure out where to get it ...
\
:ro)

I have the same chirp as the original poster, I couldn't have described it any better. Mine started on the way back from lunch on Tuesday and it's been driving me nuts ever since.

I don't think it's the AC compressor, because I let the truck idle with the hood up, and as the climate control cycled the AC, it wouldn't ever chirp. As a matter of fact, I never heard it chirp when it was idling period.

It will chirp while accelerating, driving, and decelerating, but not at idle. It could be the tensioner bearing I suppose. I don't think it's a belt issue.

The wierd thing is- and it may just be me- but it seems like it has a slight loss of power for around 1 second when it chirps... It happens so quick it's hard to pinpoint.

While accelerating, the RPM's are higher so every time the AC clutch engages it is more likely to chirp. There is a much greater difference in the angular momentum of the two. This is consistent with a slight loss of power also. --K

I believe that it is the a/c pump kicking in and out. It does it when it is not idling but driving down the road.

It's funny..... my truck did it only once. A week ago when we were
in Baja. I think my truck wanted to go home and was telling me
by strangley chirping ):h

It's obvious in my truck it's the A/C compressor or something related cycling on/off. does it routinely when A/C is on ...when I disable A/C there is no chirp.

Took my 02 in to the dealer for making that chirp noise... They found the alternater was worn down, and the belt had some cracks in it.... replaced both, no more chirp.