yes, exactly KS. i am going to take apart the air box and intake once this new england cold front passes by. idling and coasting there is no sounds so something definitely happens when the throttle is opened

 

Put a cold air intake and duals...then you wont here it...lol

 

Definitely not the fan. Mine did it when all was stock and continued to do it after I hacked up the fan and shroud when installing the body lift. The sound on mine does it only when applying certain amounts of throttle. If I only push on the gas a little (when driving) it doesnt make the sound. If I push a little harder it will make the sound as long as I keep the gas in that position. However, if I mash on the gas it doesn't make the noise either. And I have not been able to hear it when it is idling either, which makes it hard to listen closely with the hood open. I guess I could try to jack the rear end off the ground so the wheels can spin and try to locate the sound. I don't think its the air intake either, but it could be. I have a knock of K&N CAI that came witht he truck when I bought it so it is possible.

 

Is it a whistle? My stock throttle body whistled slightly when I had it on. The CAI made it more obvious, but it was always there .... normally when the throttle was at a crusing position.

 

could be...how would i check to see if its the throttle body? and if it is, does it mean somethings wrong? That would be great if it was my cause of such low MPG (12.5-13.3).

 

Sometimes they just whistle ..... mine did after I cleaned it. You can tell when you start to hear the whistle, vary the throttle a little bit. It should go away with little or more throttle and only whistle at one position. When you move the throttle around past the point of whistle, you should hear it tweeting. It will be easiest to hear when the engine is cold.

 

I just took my truck in to the dealer, this morning, to get some things fixed under my extended warranty. They told me that the front ring and pinion was bad on my truck. I dont see how that could be the cause of the noise i am hearing, but when they get the parts in, probably wednesday or thursday, Ill get the truck back and see if that fixes the problem.

Thank God i bought the maximum care extended warranty!

 

whered you buy your truck from?

 

Parks Motors of Augusta, In Augusta Ks, about 10-20 miles east of Wichita, KS.

 

I know that they are totally different systems, but my work truck (6.7 cummins) does the same exact sound, but it also does it when decelerating with the exhaust break on. I have come to some what of a conclusion on it. It seems to happen when ever the exhaust pressure is at a certain level.

Of course the exhaust pressure with a turbo is much higher, but let me ask you guys this. Do you notice a stronger exhaust smell at all? Particulartly up towards the front of the truck when idleing, or even in the cab while driving?

Just a thought.