I have a whistle coming from (it seems) the right front of my truck, only through a certain throttle range. It sounds like bad brakes, but it never comes on when i am hitting the brakes and there is no brake drag to a certain side so lets rule that out.

I almost want to think it's intake whistle, because its only through a specific range of acceleration (if i push the gas pedal down about 2 inches and hold it there is the only time, any more and it's gone, any less and it's gone)

If I drive around with OD off, it makes the noise less, i feel because in OD the RPMs are lower, than when in 3rd at certain speeds. but I'm no mechanic so I could be wrong about that being the fix/problem.

Has anyone else had an issue like this? what was it and how did you solve it?

I'm lost, and its been there since I got the truck

 

I do know that many 4.7 engines get this but usually in a Ram truck its the IAC Is what I have seen.

Have you put on an aftermarket air intake if so that could be it also the stock air intake is made to keep things quiet removing it gives you a hissing sound

 

Does it make the noise while revving it in N?

 

No it does not make the noise when revving in neutral.

 

If the noise is happening while you're driving, I have a few things, mainly because I had a similar problem. The higher revs only mask the noise in this situation. Application of the brakes will compress the shocks because of load shifting as you decelerate so no noise can occur as the shocks do not extend. When the pads and rotors are actually pressed the warning squeak/noise won't occur because the whole pad has made contact. So that is why the squeak may not exist under braking.

I had two things can done to fix the issue:

1) New shock absorbs, worn out shocks can make sort of squeak noise when compressing and extending slightly in normal street conditions.

2) Brake pads, if you bought eco pads or economy brake pads, I can't remember the name my idiot parents had them installed. I upgraded it to towing and extend wear pads. Bad/improper/worn out pads, can scratch rotors and a metal on metal squeak/noise occurs as a warning.

Personal note here too, new shocks (I have Monroe reflex up front and Monroe load assisting in the back) plus the different brake pads, made for huge ride and handling improvements, $600 I am now very happy I spent.

I hope that all helps,
Duncan

 

I got a whistle when cruising in cooler climates. Never noticed it in the summer only winter when I'm going like 40 or 50 just maintaining the speed limit.

Coming from intake I'm sure.

 

Serpentine belt idler arm bearing? You might hear it much better when going up a hill next to a wall. Sounds louder when under load (accelerating).

Just my thought... $.02

 

Sounds very loud next to a wall, it's definitely coming from the passenger front side of the vehicle, what are other signs of the idler arm bearing going?

I don't think it's shocks (but she could use a new set) and the brakes squeak every once in a while, but this doesn't seem like the brakes as I said it's when I'm driving, not when I'm braking.

It's during very slight acceleration, not hard, and always at the same point in throttle pressure/opening.

 

Remove and Clean the throttle body and give the IAC a good looking over I remember a guy had the same problem last year and the IAC was the problem he said a sleeve on the IAC shaft was lose he replaced the IAC and no more problem.

 

DAKAZ is likely on the right path, and I'd hate to waste your time.

For giggles, watch the idler arm with the engine running. If it hops or twitches at all, that's a problem. I don't know if spraying WD40 in there would temporarily quiet the bearing.

Here's another test:
With someone you trust, have them apply the brake, put in D and put the engine under load by reving it. With you on the side of the truck (not the front) watch and listen; you should be able to focus in a little better on where the sound is coming from. You may need to remove the fan to eliminate that noise.

Good luck!