My 08 sounds like a train whisle for about 20 seconds when cold i swear its intake also.
I also noticed installing s+b intake last week no gasket of any kind for the mass air.

I'd give anything to have a noise only at startup, or only when it's cold for awhile intermittent before going away. In fact, when it's cold my truck does have a high-pitched whistle-like sound, short little bursts here n there before warming up and going away. I could care less.

My engine howl is a constant noise that never ever goes away while I am giving my '04 gas, whether 5mph or 75mph. :mad: The noise goes away completely when I let off the gas pedal. Nice and quiet truck at idling, or coasting.

But as soon as I barely start to give it gas, here comes the horrid loud whine again. :mad: And it never lets up as long as I am stepping on the gas pedal, whether it's a gentle push or a hard accelleration or going fast on the highway pressing decently, no matter the speed or pressure of my foot, if there is any gas at all being given my truck makes a constant horrid engine whine. I absolutely hate it. It's literally going to force me to buy a refreshed '09 just to get the heck away from the constant whine. :mad:

Today was the first time my truck has had this annoying whistle. Of course, it was -19 this AM too. My truck is garage kept and has 18,000 on it. The whistle happens right around 2000rpm while lightly accelerating. Once the truck was warmed up, it stopped.

Not a big deal IMHO. It seems pretty obvious that it is clearly related to the components under the hood being extremely cold and expanding ever so slightly while warming up. Keep in mind that the air is significantly denser too.

My truck has been doing this for the past month. It has happened a couple times while i'm warming up the truck, and i could actually hear it from inside my house. And when i'm cruising down the road it will just start to whistle, it will get louder and louder and then stop. Also, if i take my foot of the gas, the whistle will always stop. It's a rather annoying problem.

Guess i'll take it in to the dealer since it's under warranty still.

Have a 08 F150 SCAB, the whistle has happened to me about 5 times.

If I didn't let the truck warm up for longer than 5 minutes, the whistle would go on when I pressed the brake..

Nothing to be worried about I guess, only happens when it's really cold and I dont let the truck warm up..

When I get on it, mine whistles too, but it does it all the time. :p

My truck did that only when it hit -30 oC, but i have not heard it since it has got warmer

Sorry I couldn't resist.

Does it sound like this whoo whoo!

http://www.youtube.com/watch?v=ccgXjA2BLEY

Add me to the list of the high pitched whistle for whenever the temp gets around 20 degrees or less.

So is there really any negative effect to this? yeah it does it when its really cold....did it last night when i was driving 0 to 5 degree temperature in NJ and it was very annoying....people tell me just to do a loud exhaust upgrade so I don't hear it but I'm worried about whatever damage this maybe causing or if theres any solution to fix it.

Seems to me this is a fairly common problem with 150's. Mine has done this as well the past couple winters regardless of how warmed up the engine is. But it does only occur in the winter, say below freezing and right around the 60 mph range. I normally drive 65 so it is not making the noise at that speed. Its quite loud. the first time it happened it sounded like it was coming thru the radio until i turned it off and it was still making the noise. If I hard accelerate, it doesnt happen, only under normal or slow acceleration. 05 crew.

previous posts suggest that it was the alternator but I would just like a confirmation on this. I don't feel like paying a ford rep 100+ to diagnose it like they did with my tranny shifting being off center....(its because of your lift so you need a longer trans cable) <--- waste of $100 for me :(

Knock on wood.....but mine has not been doing it lately.....and it was -25 the last two mornings.....

Sounds to me...........
 

I am thinking that we all have similar problems but different causes. I have an '08 F150 that squeals like a pig when the temp is below freezing. The colder it is, the louder it gets. But only in the 1200 rpm range +/- 200. When the truck warms up the noise goes away. The noise has changed from a whistle to a squeal. The first few times I heard it I thought it was intake related. Now it sounds like a bearing squealing. Here is a link to a thread about the same thing with a TSB #: https://www.f150online.com/forums/3514966-post11.html

I will be taking it to the dealer after deer season is over next weekend. I'll let you all know what they tell me. Interestingly enough, I have an '02 Honda VTX1800 motorcycle that fouls plugs. But only two of the four plugs get carboned up. It has two plugs per cylinder and is a V-twin. The web forum for that bike raged on about the plug fouling issue. Instantly everyone "had it" and demanded a recall from Honda. After a few months we posted pictures of what a fouled plug looked like for comparison. Now about 85% of the people that had fouled plugs could see that the plug was dirty, but not fouled. Some had a genuine problem. The carbon had closed the gap on the plug. There were a dozen "causes" and ten times as many fixes. There were legitimate problems with the main ground wire on some bikes which Honda fixed. Other people blamed the painted body of the coils (bad ground). One guy actually had improper cam timing from the factory. I may get flamed here but I believe a large cylinder (55 cubic inches) has a poor flame propagation and Honda tried to get a better burn and emissions with two plugs.

Anyway, my point is that we may not all have the same problem, just similar ones with similar symptoms.:thumbsup:

"We go for decoration, at all it is decoration"

Oh brother :rolleyes: