High-Pitched Whistle?

[TG]

Have a 2003D/A. I have noticed what appears to be a high-pitched whistle that occurs between 1500 and 2000 rpm in each gear, and varies with engine speed. Not real loud, but noticeable and a bit annoying. Anyone else experience this? Any ideas on how to stop it (besides turning off the engine)? :D If not, I'll stop by my dealer.

Many thanks!!!

TG

[AlanL]

Is it the Turbo?

If you want to eliminate the whistle, you could always remove it. tongue.gif

[schnier]

Your air conditioner also makes a dron/whistle at the RPM's stated.

[hogbody]

I have a 2003 also and I'm getting a whistle. First thought it was through the sound system....then thought it was maybe me (bats in the belfry). I didn't notice it when first bought the truck but my theory is it started after I started adding accessories, ie; transferflow tank (w/computer), cb, and remote cell phone charger. Been thinking about unhooking it all and checking.

Love the truck

Larry

[hoot]

The turbo emits a high pitched whistle that changes with rpms.

Sometimes when adding accessories, you hear it more through holes you may have drilled for wires/hoses.

High frequencies are tricky. Some people will hear them while others can't.

And yes, some electronic devices either emit high frequency sounds or emit electromagnetic noise that will come out elsewhere like a sound system, even when the soundsystem is turned off or volume is down.

[ 02-20-2003: Message edited by: hoot ]</p>

[FisHn2DMax]

Sounds like the Turbo!

The Turbo runs up at a very high RPM, this creates a very high frequency audible "Whistle" inside the cab at or near the top end of our hearing range, especially when at or above 1600 RPM. Below this RPM, it's not quite as obvious, but it's there, just lower in frequency.

They all do it and it's all very subjective tot he driver! The drivers individual hearing range determines how loud or annoying it is. If you have good high frequency hearing it's worse! My kids can all heard the Turbo "Spooling up" sitting in the back seat the first day I had the truck, My wife and buddies can't hear it, but I sure can! When I first got the truck it drove me nuts, now I'm used to it. If the Turbo whistle starts to bug me, I just turn up the stereo.

Good News: You just passed your hearing test!
Give yourself another twenty years, attend a few more rock concerts, Straight pipe the Harley, and you won't have to worry about that "whistle"...LOL. ;)

[johnpugh]

It's not the turbo. In my '03, I have heard the same sound in combination with the turbo sound. It sounds electronically generated. Possible some of the new electronics on the 03's are causing this.

I've learned to tune it out....

Of course, after reading this post, it will probably be louder than ever.....

Later

[c5dura]

Hmm, I've had a high pitched whistle ever since I got my truck back from the shop after running it into a ditch.

Prior to the incident, I only heard the turbo whistle, which is an even higher pitched sound that I don't mind.

Ay first this new whistle was VERY loud, but has since calmed down quite a bit, but its definately still there. This new pitch, however, only comes when I'm more or less WOT pulling heavy loads, going up hills, or accelerating hard, and only above 1800 RPM or so.

It has been suggested that it might be a idler pulley or accessory, but if that was the case, why don't I get the sound all the time when above 1800 rpm?

My personal theory is that my turbo is not what it used to be (I sucked muddy water though it during my trip into the ditch), and under max load, it starts to make this secondary whistle sound.

I'd like a ride in another dmax to verify that this sounds isn't 'normal', but I swear I did not have it prior to the accident.

Btw, I'm back to the stock intake for the time being until this issue gets resolved to rule that out of the equation.

[ 02-20-2003: Message edited by: c5dura ]</p>

[RVGuy]

I've heard something similar to what's being described. It is NOT the turbo. What I'm hearing on occasion, is very faint high pitched squeel that I would assoicate with alternator noise in a radio.

But the radio is turned off while hearing this. It isn't bothersome to me. In fact, I'm surprised I even hear it as I usually can't hear my wife when she talks. tongue.gif ;) :D

[TG]

Alan and Fishn,

Very funny! :D :D

Somehow, it slipped my mind that I have a TURBO diesel - duhhhh. The noise is noticeable only when I have the radio off, so I am guessing it is not electrical, and is probably the turbo.

Thanks to all for the responses!! It sure is nice to be able to ask questions and get some expert replies.

Best,

TG smile.gif

[FisHn2DMax]

RVGuy,

After reading your post and others here with regard to another potential source of a whistle type noise (other than the obvious turbo spool whistle), I remember hearing a very soft but high pitched sound after coming home and shutting off the DVD rear ent. system the kids were watching. It was wierd, with the engine running at idle, the sound was coming from the speakers, but the CD,AM,FM and DVD stereo was turned off? Then I realized the 03's have a power amplifier that is hot all of the time if the key is in. Sitting in the drivers side, I could hear the tone very clearly, then I shut off the engine, the sound went away? When I started the truck again, the sound came back and seemed to vary with engine RPM? I thought it wierd and kind of forgot about it, until your posts.

I haven't heard it again, but it does tell me that EFI noise could be getting in to the power amp and into our speakers, even if the dash stereo is off! The 03's ( mine has the factory Bose system) have a seperate power amp that is on all the time for the door chime, key, Lights, and other audible chims. In 03's, all audible warnings come through the door speakers ( no buzzers).

I think you guy's could be on to something? I'm thinking there could be EFI/EMI noise from the engine injection system some how getting into the power amp? Many things can cause EMI noise, bad grounding, poor amplifier shielding, to as simple as a loose connector.

This won't be an easy problem to find!

BTW, My Turbo spooling whistle sound is a totally seperate and a distinctly different sound then that of the high pitched sound I heard coming from the door speakers? I tried to emulate the sound again tonight, but couldn't duplicate it? ;)

[ 02-20-2003: Message edited by: FisHn2DMax ]</p>

[conradv]

Hmm.. My wife cannot hear my turbo's whine while I can, and I even had her put her head down (easy you guys) next to the door's Bose speaker and she couldn't hear anything.

So in my GMC '03 I came to the conclusion that my whine is definately the turbo, and not any electrical noise. (Just wanted to post my findings..)

p.s. - I LOVE that turbo whistle! I even punch it now and then just to hear it...

[RVGuy]

FisHn2DMax,

I agree. Although my noise has been less apparent than once was. Which seems a bit strange also. I don't have the upgraded stereo/radio so, in my case I can eliminate amplifiers, etc.

My problem too, is that I can't localize the sound. It seems to be coming from everywhere. That could be a clue that its coming out of the speakers. :eek: :eek:

I'll keep you posted and you do the same if we come across something on this.

[ 02-21-2003: Message edited by: RVGuy ]</p>

[MountainMax]

TG if what you're describing is the turbo, we don't call it a whistle on this page,.....

We call it music :D