A/c Squeal When Turned On?

dcontarino · September 7, 2008

Over the past three months my HD has developed a squealing noise that occurs randomly when the A/C is switched on. Turning the A/C and blower off, then back on, resolves the problem. It happens about three times a week.

My first guess is that it's some kind of belt problem, but aren't those sort of things extremely rare in 2008? LOL Any guesses? And anyone else had a similar problem?

I ain't too worried because of the warranty. Curious more than anything else. Thx.

Kodiak450 · September 7, 2008

The bearings in the clutch could be bad, they would make a squeeling noise often confused with a bed belt. But I wouldn't rule out a bad belt. I would have to hear the noise myself to determine what is causing it.

Zembonez · September 7, 2008

Sounds like a glazed belt to me. It's pretty common. I know I went through about 4 belts on my 2001 truck because they got noisy. They didn't look bad but I couldn't handle the noise. Same thing happens on my company car Explorer about every 20K.

minibike132 · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

2000DV4.8 · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

+1,000. Don't spray WD-40 on it either. I have no idea what people are thinking when they do that, but it happens more than I could ever imagine.

Mikeee · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

+1,000. Don't spray WD-40 on it either. I have no idea what people are thinking when they do that, but it happens more than I could ever imagine.

From the WD-40 website page listing 2000+ uses.

"Stops belt noise on automobiles"

http://www.wd40.com/uses-tips/category/aut...orts-boating/3/

minibike132 · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

+1,000. Don't spray WD-40 on it either. I have no idea what people are thinking when they do that, but it happens more than I could ever imagine.

From the WD-40 website page listing 2000+ uses.

"Stops belt noise on automobiles"

http://www.wd40.com/uses-tips/category/aut...orts-boating/3/

The makers of WD-40 may endorse it but I don't. I've had alot of extra problems caused by customers spraying all kinds of stuff on belts and WD-40 is one of them. WD-40 is a fine product, I'm not bashing it, and it will stop the squeek but stopping it that way comes at a price.

2000DV4.8 · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

+1,000. Don't spray WD-40 on it either. I have no idea what people are thinking when they do that, but it happens more than I could ever imagine.

From the WD-40 website page listing 2000+ uses.

"Stops belt noise on automobiles"

http://www.wd40.com/uses-tips/category/aut...orts-boating/3/

Common sense should tell you not to spray it on a belt. Why do belts squeal? Because they slip. WD40 is a lubricant. Yes, it gets rid of moisture, but it's still lubricant.

dcontarino · September 7, 2008

Hard to say without hearing/seeing it but what ever you do don't spray anything (belt dressing) on the belt.

+1,000. Don't spray WD-40 on it either. I have no idea what people are thinking when they do that, but it happens more than I could ever imagine.

From the WD-40 website page listing 2000+ uses.

"Stops belt noise on automobiles"

http://www.wd40.com/uses-tips/category/aut...orts-boating/3/

Common sense should tell you not to spray it on a belt. Why do belts squeal? Because they slip. WD40 is a lubricant. Yes, it gets rid of moisture, but it's still lubricant.

Right. I ain't a dumb brick LOL But I can see some ditzy person doin that. Guess I'll bring 'er into the stealer and see what they say... "sir, you also need a tune-up and new tires and a new headliner"

Kodiak450 · September 10, 2008

WD-40 spraying on squeeky belts sounds like a corrupted used car salesmen tactic.

SS Crew · September 19, 2008

My truck has done the squeel about 3 times, but has happened when I used the remote start. My A/C is always on and doesn't make any noise while it's running. The squeel only lasted maybe a second. It hasn't happend in a couple of months, but I checked my belts and they seem fine, no cracks or glazing - so I don't know what's going on. But it doesn't sound like I'm the only one that has had this happen.

dcontarino · September 19, 2008

One thing I've been able to associate my squeal with is extremely hot weather. In the past week, SE TX has been "cool" with highs in the 80s and low humidity vs. close to 100 for the summer. I haven't had the dang thing squeal in over a week now. So I think it has something to do with sitting in the sun and/or high humidity... I have an appt. to bring 'er in to the dealer next week, though. I'm sure that the problem won't be able to be duplicated as is usually the case.

pm26 · September 29, 2008

Does the truck have a separate A/C belt like my '06 Z71 does? Does the belt have a spring loaded tensioner?

Squealing when turning A/C on is almost always caused by a belt that is too LOOSE. I have this problem occasionally with my Mazda 626. If your truck's A/C belt has a spring loaded tensioner, the tensioner spring could be too weak. I would say replace the tensioner and the belt under warranty.

dcontarino · September 29, 2008

Does the truck have a separate A/C belt like my '06 Z71 does? Does the belt have a spring loaded tensioner?

Squealing when turning A/C on is almost always caused by a belt that is too LOOSE. I have this problem occasionally with my Mazda 626. If your truck's A/C belt has a spring loaded tensioner, the tensioner spring could be too weak. I would say replace the tensioner and the belt under warranty.

Thanks pm26... The squeak hasn't occurred now in about 3-4 weeks since the temps are no longer up at 100 during the day - closer to 85 now. Does rubber expand with heat like plastic does? If that's the case, perhaps the rubber belt does expand and become loose. Either way, thanks for the suggestion. I may have to wait until next summer or the next hot day to bring er in for service now that the squealing ain't happenin.......

pm26 · September 30, 2008

Even if the belt expanded slightly, the spring leaded tensioner (if your truck has one) should take care of the slack. It is also possible that you get water vapor condensation on the pulleys and the pulleys are slick until the water dries up. Which would explain temporary belt squeal. Do you live in a high humidity region?

BTW, do you have any complaints about the new 6 speed auto transmission, like hesitation when down shifting at low speeds?