06 with 12K just started th whistle thing this past weekend. Very annnoying and my wife freaked and said we needed to pull over before something broke. I watched the gauges and kept going. Once off the grades it is fine like everyone else says.

 

I tow an 18,000 lb fiver with an '06 6.0L LB CC 4x4 Dually auto tranny tow boss.

On my recent 3800 mile trip I had the sound described in this thread under the hood. I recorded the noise to take to the dealer since I know he won't be able to duplicate it without going on an extended vacation with me.

Here's what I'm taking to the dealer:
Noise sounds like an old fashioned bell telephone or tea kettle ringing under the hood.
Occurs only when towing for extended periods (engine warmed up), and only when in the mountains.
Does not matter if A/C is on or off. Does not matter if Tow/Haul is on or off.
Oil, transmission temperatures and oil pressure gauges read normal mid range. No unusual indications on the dash read-outs.
Initial speed 55 - 60 mph. Downshift indicated below at 50 mph.

Sequence of events:
Climbing a hill.
Truck downshifts at 50 mph.
Engine cooling fan comes on.
Fan runs for about 5 - 10 seconds.
Fan noise gets quieter, but is still heard.
Ringing noise starts, lasts about 5 seconds, and stops.
Fan resumes high speed noise for about 5 - 10 seconds.
Cycle continues until reaching the top of the hill.
Truck upshifts at 55 - 60 mph.
Fan noise and ringing continue until fan shuts off.

It's not the fan clutch as mine was replaced between my last two trips - unless I got two bad ones in a row.

 

I wonder if there could be some kind of a harmonic phenomina going on here, somewhere with the fan clutch or belt/pulleys?
Has anyone tried belt dressing???
Just a thought.

 

Tim--check out this thread real quick: https://www.ford-trucks.com/forums/6...ford-cant.html

 

NO BELT DRESSING!! At least im not the only one who thinks of the (dumb) ideas and gets a slap on the hand! Learn something new every day! God I love this forum

 

Ford probably knows exactly what the fix is, but doesn't want to come out with an upgraded clutch assy. if in fact that is the problem. And since it only happens to those towing heavy on long passes, seems like not enough people bitching to get FOMOCO to care about a REAL fix. ANYTHING can be fixed, modified or replaced...CMON Ford. A guy at the local dealer has been complaining about this for over a year. He finally got a new clutch assy. He is taking his Hauler out in a week or so. I'll call the dealer and find out what the deal is....From what I gather this dude is on a mission to get it resolved.....This is probably the only "thing" I HATE about my truck. ~!Brad

 

I'm on my second fan clutch and it didn't help. I looked at the fan clutch and thought for sure that it was a harmonic problem. At the front of the clutch assembly where the wiring harness is attached, there are two pieces of sheet metal held on by a rivet. I was thinking that a poor rivet job could let those two metal plates vibrate harmonically, but I find it hard to believe that two fan clutches could have the same problem. Besides, the first trip we took under the same circumstances (same route, same trailer, same truck) with only 5,000 miles on the truck didn't have a problem. The second trip was where I had the problem for the first time. And the third trip, I still had the problem with a new fan clutch installed.

So I don't believe it is the fan clutch.

One guy I've talked to said his stealership was going to remove the belt and sandpaper all the pulleys to roughen them up to prevent slipping. I'm sorry, but that sounds like a BS fix and I wonder what it will do to the life expectancy of the belt?

 

Hmmm, that's interesting. What I read there was that belt dressing would make a mess.
If the mess is the concern, I have also heard of using a bar of soap, holding it under the belt (CAREFULLY) while engine is running. I don't know if it would be easy with the 6.0, as there is very little room under my hood, but if it can be done safely, it might be something to try, just to see if it is belt slippage. If it quits squealing after applying soap, that would narrow it down.
My truck is at home, and I'm at work until tomorrow. I'll have ta take a look when I get home, to see if it is possible.
What do you think, good idea or?.....

 

https://www.ford-trucks.com/forums/6...hlight=coolant

https://www.ford-trucks.com/forums/4...hlight=coolant

 

bnmccoy,
I am not loosing coolant at all. The level holds right where it is suppose to be. There was a recall done about a year ago where they put a new full line on the degas bottle. It was said that allot of suspected head gasket issues were actually trucks that were overfilled with antifreeze, and barfed coolant when heated up under load.
(i wonder how many head gaskets were changed for nothing?)
Mine is filled to the new lower level, and doesn't loose any coolant whatsoever, so I don't think mine is a head gasket problem.

 

bnmcoy. same here. I've got mine filled to the lower level of the bottle as advised by the service manager at my dealership. No changes in coolant level at all.

 

My 05 just started doing the same thing. Loud fan noise on steep grade while towing in 80 degree weather. Wondering if I should be concerned or just keep an eye on it.

 

If it just a fan noise, then I wouldn't worry about it. That is normal. Kinda scares the heck out of you when you first hear it. The whistle refered to here sounds more like a tea pot. Judging by how many folks are having the same whistle sound, I imagine that it is also not too much reason for concern. Just annoying is all.
I don't floor the accellerator as much on steep hills anymore. Takes just a little bit more time reaching the top, but it hasn't done the whistle thing lately since I changed my driving habbits.

 

Mine just started whistling under load recently as well. The symptoms are exactly as described in this thread. Moderate to very steep hills and the tea kettle noise begins around 2200 rpms.


Has anyone been able to pin point the exact source of the noise and correct it?

Thanks.

 

I never bothered to take mine back to the dealer after the last trip. I may just wait until I retire in March and then sometime this summer, find a Ford dealer in the mountains and ask the service manager if he wants to see a Ford Super Duty squeel under a load.