Quiintin,

Solved the whistle problem last night. Slapped in a Ford remanufactured alternator - just like some of the posters said in the '04-'08 forum. The silence is golden!

Quintin,

As you suggested, I gathered some more information for you on my whistling truck. First, here’s the VIN #: 1FTRF14535NA65131. That should come back to a 2005 XLT regular cab / short box 4x4 with the 5.4 liter motor.

Next, I tried to see if I could make the noise appear with the truck in Park. Much to my surprise, I could. Unfortunately, nobody else was around to hold the pedal whilst I poked my head around under the hood to see if I could hear it. But, the whistle appears only below about 40 degrees – colder if it’s wet outside. (Today it’s wet and 40 and no noise. When I took the truck down to North Carolina last month, it was dry and about 40 and it whistled the whole way down.)

The nose sounds like either a whistle or one running a wet finger around a wine glass. It fades in at about 1,700 RPMS and fades out at about 1,900 RPM under light load. (Remember, the factory tachometer isn’t all that accurate.) When it happens while I’m driving, all one has to do is slightly vary the pressure on the accelerator pedal (up or down) and it’s gone. It does it when the truck is cold or up to operating temperature – again – as long as it’s cold outside. I recently replaced the serpentine belt with a Goodyear Gatorback and it had absolutely no effect.

Hopefully you can shed some light on this one. It’s really driving me wild. You’ll find numerous posts on it in the 2004-2008 forum.

Thanks again!

Tom

Quintin,
I need some honest advice from someone I can trust - like you. My '05 5.4 has 69,000 miles on it. I'd really like to have the plugs replaced before they totally weld themselves into place. My dealer advises me NOT to do it unless I'm going to keep the truck past 100,000 miles - even though they admit that the longer I wait, the bigger the problem will get. They're also saying that once a plug breaks, they're pretty much into pulling the cab to get to the heads - and Ford won't cover any of it.
Can you give me some honest advice? Thanks.

Tom