High-pitched squeal when temp. rises/fan kicks in ?

[YFZ 450 Quadaholic]

Looking for some input in troubleshooting this intermittant noise.
(My truck info. is 2005 6.0 PSD w/ 37" tires, 6" lift, Edge juice *on level 2 when towing* + SCT controlling the tranny.)
When pulling a heavy load such as my loaded toyhauler up an incline for a few miles, the fan comes on like normal....but if the fan needs to stay on for more than a couple of minutes....then I will get this loud squeal and I smell coolant. I know that this smell is probably just the degas cap spilling a little out; but what the heck is that noise??? I have to let off of the throttle slightly to cause it to stop.....so I just "feather it" just to the point of not hearing it do that - all the while loosing a little momentum. I don't see any evidence of much coolant spilling and making a mess. It's hard to describe the sound....just a constant high-pitched whine.
I am not hammering down and demanding way too much out of the truck when this occurs. Just real steady power; boost @ around 24 - 28 , tranny temp. around 190 - 200 and RPM's around 2600 during this load condition.
Thought I would ask for some feedback from you(and @ FTW) prior to going to the dealer and trying to describe it. One thought I had was having the head diesel mechanic come and ride with me when I have around 10K in my dump trailer and replicate the noise with him in the vehicle (I have a relative that works at a local Ford dealership and might be able to pull this off).
Has anybody ever had this occur or heard of it?
Thanks again,
-James

[_CH_]

Looking for some input in troubleshooting this intermittant noise.
(My truck info. is 2005 6.0 PSD w/ 37" tires, 6" lift, Edge juice *on level 2 when towing* + SCT controlling the tranny.)
When pulling a heavy load such as my loaded toyhauler up an incline for a few miles, the fan comes on like normal....but if the fan needs to stay on for more than a couple of minutes....then I will get this loud squeal and I smell coolant. I know that this smell is probably just the degas cap spilling a little out; but what the heck is that noise??? I have to let off of the throttle slightly to cause it to stop.....so I just "feather it" just to the point of not hearing it do that - all the while loosing a little momentum. I don't see any evidence of much coolant spilling and making a mess. It's hard to describe the sound....just a constant high-pitched whine.
I am not hammering down and demanding way too much out of the truck when this occurs. Just real steady power; boost @ around 24 - 28 , tranny temp. around 190 - 200 and RPM's around 2600 during this load condition.
Thought I would ask for some feedback from you(and @ FTW) prior to going to the dealer and trying to describe it. One thought I had was having the head diesel mechanic come and ride with me when I have around 10K in my dump trailer and replicate the noise with him in the vehicle (I have a relative that works at a local Ford dealership and might be able to pull this off).
Has anybody ever had this occur or heard of it?
Thanks again,
-James


i know EXACTLY what youre talking about..... and what it is :D ill post a sound clip of it later tonight if i can convert it to a .wav

i have yet to figure out a way to fix it - going to talk with froggy about it soon. What it is: :upyours: boost/pressure leaking out of the degas bottle. :upyours: I used to think i had a boost leak, but now i know for sure it’s the cap/bottle leaking. Usually its accompanied by a smallish loss of coolant as well.
Ive even heard it idle before (and recorded it) - try shaking the hoses that go into the degas bottle - it might exaggerate it or it might mitigate it a bit - either way you can confirm what it is

[mikeym]

sounds like some more clamping force in the degas bottle top would solve the problem. silicone that bitch shut!

[_CH_]

sounds like some more clamping force in the degas bottle top would solve the problem. silicone that bitch shut!


no shit man! im going to try some teflon tape on it - but i hear tell that not all the caps hold the same pressure (crap quality control :upyours: ), thus some do it some dont. if the tape wont fix it i guess ill be getting another cap

[jello]

Is this the sound?http://video.thedieselgarage.com/video/b5d92c67-822b-4df3-8e5c-986300a324c6.htm

[_CH_]

the sound after the turbo fart? if so.... then yes thats it

[Carssuck]

My 03' made the same noise going down the hwy pulling my trailer and never puked one drop.
The truck had a tough time building 25 psi. Are you guys saying that may be the head gasket leaking boost, or just the degas bottle venting pressure from the extra heat of working hard?
It only did this with certain SCT files, never with Doug's.

I sure am glad I dumped that thing now! Another gasket job would have sucked!

[_CH_]

My 03' made the same noise going down the hwy pulling my trailer and never puked one drop.
The truck had a tough time building 25 psi. Are you guys saying that may be the head gasket leaking boost, or just the degas bottle venting pressure from the extra heat of working hard?
It only did this with certain SCT files, never with Doug's.

I sure am glad I dumped that thing now! Another gasket job would have sucked!

as far as i know my gaskets are fine: ive had my head up to the bottle when its making the noise and (at least on mine) thats where its coming from without a doubt.

[Carssuck]

as far as i know my gaskets are fine: ive had my head up to the bottle when its making the noise and (at least on mine) thats where its coming from without a doubt.

Does it do it stock?

[_CH_]

yup, a lot of the time it will. not 100% of the time... but enough
i sure dont have the problem your old truck did tho - i can make 25#s no problems

[YFZ 450 Quadaholic]

Thanks for the replies guys. I will check this out regarding the degas cap.
I have another suggestion on FTW forums that it could be the clutch fan. So now I have two real good leads. The sound file is close to mine; but mine is alittle higher-pitches than that. I am hoping that it is not the turbo going out and even more hopefful that it's not the head gasket. Doug - what do you think???

[PSDPlayer]

Make your life easy and stop guessing. Get a pressure tester and rig up a T fitting in line with the hose comming from the intake manifold to the bottle. What is the pressure when the noise is being heard? If its 16psi then the cap is doing its job to bleed the extra pressure. It has nothing to do with the threads on the cap. It vents around them. If you silicone it on you are mentally retarded.

[mikeym]

If you silicone it on you are mentally retarded.

so what are you trying to say doug? :upyours:

[heinzboy]

so what are you trying to say doug? :upyours:


I think what you just wrote CLEARLY states the facts Mikey.

[mikeym]

go run a 14.97 or something...

[heinzboy]

go run a 14.97 or something...

Get on your knees and do what you do best. :upyours:

[mikeym]

you would like that wouldnt you, fag.

[YFZ 450 Quadaholic]

Doug,
Mine will not do this in nuetral with the RPM's up. It ONLY does it pulling heavy trailers up hills for extended periods of time. Do you think it is most likely the clutch fan??????

[Phoneguy6.0]

I came home from West Palm last night and I startred hearing a high pitch whistle but only when I'm coasting or standing still. I had my up tube replaced because of a crack in the flex section which caused a loud whistle under load. I'm going to Moroso tomorrow so I need to find the source before I go down the track.