great news..I'll have my alt replaced and a new Gatorback installed as well.

Yeah, like an idiot I forgot to bring my Gatorback belt with me and ask them to put it on instead of the stock belt. That would have saved me an installation cost. I left it sitting on my work bench.

I guess it'll just have to sit there until I start hearing the stock one slip. Everywhere I've called wants $60 to put it on, which is not worth it in my mind.

Does it hurt the belt (dry it out) to just have it in storage?

Duke

I just heard the same whistle today it was 25 degrees on the way to work and I was cruising at 45 when i heard a whistle noise it started out quiet and then got really loud. Almost like I was passing someone on the side of the road using an electric leaf blower. But like everyone is saying if you let off the gas or punch it it goes away...atleast for a little while.

Harmonic whine gone
 

I am in Ontario Canada, about an hour west of Ottawa. I have a 2004 FX4 5.4 and had that annoying whine while driving at below freezing temps. It sounded like running your finger around the top of a wine glass. We tried everything form the windshield to the cowl below it and various stuff under the hood and no fix until trying a new alternator. I have been driving for 2 winters now and have not had the noise return. I have 110,000 km’s on the truck now and no noise problems.

Temps have been in the 0 to – 30 F range up here lately!

Hope this helps….

I am west of Ottawa as well and just booked it into A&B to get it fixed.
I will let you know if it clears up.

Hello all,
New member here. I have a question regarding the alternator replacement. What are members using for replacement? rebuilds, aftermarket, ford parts???

Engine Whistle
 

I had the tensioner replaced which got rid of some of the whistle. Next, Ford replaced the alternator. No more whistle. Talk to one Ford dealer that said they have replace the alternator in about 1/2 their 04 F150s that they have sold. It is a common problem.

I ended up with a rebuilt one but now it is so faint I have to focus to hear it. Maybe I will look at the tensioner as well.

When I mentioned the alternator thing to the tech at my dealer, he acted like I was crazy. He said that he would have had a "lot" of them to fix if there was an alternator problem.

Meanwhile, we have been above freezing for a few days and no whistle, no loss of acceleration. This morning, it was below freezing again and the whistle was back. It hit right at 50 mph this time and lasted for about 10 seconds, then it was gone after the truck warmed up...
It will be sub-freezing again in the morning, so we'll see what happens.

Still doing it. For those who have had yours fixed, can anybody give any specific information I can give the dealer about the problem.

My dealer replaced my alternator and the problem is gone. They have seen plenty of them and knew what it was when I called.

Interesting news from my dealer - whom I happen to trust. When I described my syptoms, the big question they had for me was, "Does the noise stop when the truck gets up to operating temperature?" In my case, the answer was that it does not. They then told me that the official word from Ford is that if it does stop when up to operating temperature, it's the alternator. If it does not, it's in the intake and there is no known fix - yet. Once again, it sucks to be me. Oddly enough, the temperature cracked 40 F yesterday and the noise was gone.

Well, let me add my truck into the list of "whiners".

2003 Fx4 Screw

Picked it up this past summer. 41,000 miles

Has 43,000 now, and the temp has dropped below 40 degrees.

Since then at what seems to be the top of EACH gear I hear
this loud whining. Starts out quietly then gets louder and
louder until the vehicle shifts, then all is quiet again until
the next gear change.

Only occurs until the truck is fully warmed up, and does NOT
occur when it is warmer that 40 deg out.

Will be contacting the dealer later this week to see if they
can diagnose for me. Vehicle was a Ford Certified Pre-Owned
so they seem to bend over backward for anything I need.

Thanks

Rod

Add me too. Recently had cold temps down to -6 F. Whistled like someone boiling water for tea on the stove. Intermitten till the truck warms up. Very loud and obnoxious. Mine does not do it unless the temps are below 10 degrees.

The mystery continues.....:coffee:

Mine does this too, every winter for the past two years that I have owned it. Only when it is cold, like 20 degrees or below. It only makes the sound at a certain RPM. On Saturday I drove to my parent's house, about an hour away. Had the cruise set at 68mph and around 1800-1900 RPM's and it would whistle non stop. If I would go a couple of mph faster or slower the whistle would stop. I actually had the truck at the dealer 2 years ago, a couple of months after getting the truck and still under warranty, because the e-brake was sticking and I rode around with the tech trying to duplicate the problem with the e-brake and he noticed the whistle as well. He wasn't sure what the cause was and I wasn't too concerned with it at the time. The truck runs fine otherwise so I will just let it be.