Whistle In Cab

[ebc]

Hello,

Recently, my 2001 Silverado 2wd has developed a high pitched wheeze that is directly proportional to engine speed. It is loudest in the cab and is louder in damp weather. It can be heard under the hood but not as well. I listened to the alternator bearings with a stethoscope but that was not the source. Ditto for the PS pump, belt tensioner and idler pully. I was thinking a vacuum motor leak in the AC system. Any thoughts?

Thanks,

ebc

[Letcher]

Sound like a dog whistle just off idle and gets louder? Can you hear it best when the HVAC is off and the radio is off? If it does then then I have the same problem and I have a new 2007 Silverado. There is no fix as of right now according to the dealer, but they do say it's a known problem. They say there isn't a fix. I wonder if the techs here can shed any light on the subject.... Dealer actually said it was the "steering gear"... not the pump

[ebc]

Letcher,

Since my last note, I found that the belt idler puller (not the tensioner) had a worn bearing. After replacing it, the sound is barely noticeable. The source of the sound is somewhere around the plenum. Since the truck is running OK, I just ignore it.

For a new ride, I would be PO'd with such a noise. Hope they get it right for you.

ebc

[jlcallaway]

Hello,

Recently, my 2001 Silverado 2wd has developed a high pitched wheeze that is directly proportional to engine speed. It is loudest in the cab and is louder in damp weather. It can be heard under the hood but not as well. I listened to the alternator bearings with a stethoscope but that was not the source. Ditto for the PS pump, belt tensioner and idler pully. I was thinking a vacuum motor leak in the AC system. Any thoughts?

Thanks,

ebc

 

Is it doing it while at park or while on the road? My 2001 HD 2500 Whistles which I keep being told is the rubber flexible molding that is around the windshield. it seems to be very load.

 

JoJoJim

[krww06]

Sound like a dog whistle just off idle and gets louder? Can you hear it best when the HVAC is off and the radio is off? If it does then then I have the same problem and I have a new 2007 Silverado. There is no fix as of right now according to the dealer, but they do say it's a known problem. They say there isn't a fix. I wonder if the techs here can shed any light on the subject.... Dealer actually said it was the "steering gear"... not the pump

 

Does it sound anything like the high pitch noise you sometimes get when you add an amplifier to a car and it's not grounded properly (I think it's sometimes referred to as alternator feedback)? This is how I would describe the noise I'm getting in my '07 NBS Silverado. I really don't think it's the alternator causing my noises, but that's what the noise reminds me of. FWIW, it seems to be coming from the drivers side of the truck. It's starting to drive me crazy.

[ebc]

Sound like a dog whistle just off idle and gets louder? Can you hear it best when the HVAC is off and the radio is off? If it does then then I have the same problem and I have a new 2007 Silverado. There is no fix as of right now according to the dealer, but they do say it's a known problem. They say there isn't a fix. I wonder if the techs here can shed any light on the subject.... Dealer actually said it was the "steering gear"... not the pump

 

Does it sound anything like the high pitch noise you sometimes get when you add an amplifier to a car and it's not grounded properly (I think it's sometimes referred to as alternator feedback)? This is how I would describe the noise I'm getting in my '07 NBS Silverado. I really don't think it's the alternator causing my noises, but that's what the noise reminds me of. FWIW, it seems to be coming from the drivers side of the truck. It's starting to drive me crazy.

 

Mine turned out to be the diodes in the alternator. A guy on BITOG helped on this one. I unplugged the charge circuit and the whine went away. Off to NAPA for a rebuilt alternator. Problem solved.

Thanks,

ebc