When it's around and below, I hear sort of a whine...you know, like worn out bearings, but not really. It sounds like it's coming from one of the idler pulleys or possibly the alternator? What is normally the first to go? Truck has 123K miles on it and no pulleys or alternator has been replaced. It's all original. After the engine warms out a little, the sounds goes away and it's back to normal. I only hear this in winter, not summer.

What's your opinion?

We're taking this truck on a huge trip this summer so if something is getting close to giving out, I need to deal with it before we leave in July....or even June. Smaller trip in June. I don't think it's super close to failing completely, but it just sounds to me like something is getting worn out, over time.

 

The cold whistle/ whine is from the altenator bearings....
They just do it....if its the original stock oem factory altenator......if its really bothering you change out the altenator but other than that nothing is wrong.....

 

they all do it. mine does it, my dads 05 does it. both with less than 63k on them.

 

Like this?

(Keep your volume low, its ear drumb bursting loud )
http://www.youtube.com/watch?v=JPuw4COf1eU

That was in 2009 at 73k miles, it still does it but right now it is not as loud as it is in this video.


Its actually just like this guy's right now.
http://www.youtube.com/watch?v=rdpDiQDQUvg

 

It's pretty much like that in your first video, but I don't think mine is nearly as loud. Not at all. It's the same type of sound, but mine is not as loud.

If you all think it's not likely to leave me stranded in Yellowstone this summer, I'll just forget about it :-)

 

Mine does it too mostly when cruising around 55 mph or 1500 RPMs. It's not very loud either but enough to be annoying. Once the temperature get's above 20* outside it goes away then I forget about it.

 

I have an 04 with a 4.6 engine. I have the same sound as Darren76 has only not at idle. It occurs when get to about 35 to 40 MPH with a light throttle. If I step on it or let off, it goes away. It's done this since new and it's driving me nuts!

Darren, after that really loud session when it starts, does it do it while you're driving?

My dealer replaced the fan clutch, belt and belt tensioner and two idler pulleys. Did nothing.

Because I can change the sound with very, very little throttle change, I'm thinking it is an air leak / whistle. I thought it was the throttle body icing up but Darren's truck screamed right away. Not enough time for ice to form in the throttle body.

I'm going to subscribe to this thread and hope someone finds the fix.

Common guys... I'm counting on ya!

 

I had exactly the same prob with mine and it was just as loud as the video (if not louder!) and lasted even longer. It's 100% the alternator bearings and definatly has to do with cold weather. The colder, the louder, the longer! Just a ford thing i guess. Replaced the alternator and high pitch wisle (and embarrasement) gone! If it even sounds remotely like that its the alternator and will only get worse with age and temp. With all the threads on this you'd think that there would have been a recall!?!

 

FINALLY

Ive taken my truck to 3 different mechanics, one of them being a ford dealership. The first one suggested it was my idler pulley, so i told him to fix it. 300 bucks later it was still doing it (wasnt happy and they knew it). So i called ford and took it in. They told me they couldnt get it to do it and that it was nothing. So i took it to a place i take all my company trucks. They thought it was because of my air intake snorkle being out of the fenderwall. NOPE. Never really thought of it being the alternator really, because like all you guys when i put a little gas on or off it goes away.

Is there any serious concern with this or will the alternator just eventually give out and thats that?

 

That's my concern...will the alternator bearings just give out on my long trip :-) The noise isn't bad right now, just a little annoying until it warms up.

 

Does it sound like this?

I took this vid this morning because there is a thread in v6 engines about a loud whine on cold start up, but on ours it sounds like power steering pump. This was the longest mine has ever done it this morning, but it was a little chilly! The sound went away as soon as I stopped the video.

 

Nope! That's not the noise. Every Ford in the world make power steering noise at startup when it's cold. Usually though, it's only 3 or 4 seconds. Your's howls far too long.

 

All this talk of it being the alternator got me to thinking... Perhaps it is the belt slipping on the alternator pulley. So today after work, I started my rig and found that the howl occurred at 1870 RPM. I opened the hood, got a can of WD40 and sprayed the belt and pulley. The sound did NOT go away. Therefore, it is not the belt slipping on the pulley.

I did notice that the alternator is making some worrysome noises. I can't imagine what, inside an alternator, could make such a noise!

DAMN! I hate to buy a new alternator! Things got only 26k miles!

 

Yes, mine does it while driving like everyone else. I just give it a little strain of low end torque to aise the rpms 250 and it goes away, but comes back if im cruise controlled at that speed. Only in the cold too.

It is the alternator bearings. Its mechanically fine for now, mine is at least. I would replace it at a high mileage area like 150k+ miles.

 

Well OK. I'm going to pick up a new (not rebuilt) alternator when I finish this post. After it's installed I'll have to wait for it to get cold outside again to see if the noise is really gone. Being here in Montana, that shouldn't be too long I guess.

It's not that I don't believe you guys, it's that I find it hard to believe that a bearing could make that much noise, be that loud, without cutting through the shaft or doing other major damage to itself.

I'll let you all know how I make out.

Thanks for your help!