Sounds almost like freon flowing through an evaporator. I can hear it inside the cab at idle, outside the cab too much engine noise to locate where it's coming from. Scoured the internets and can only find whining and squealing noises.

Any one experience it?

 

How is your power steering and brakes? First thought is the PS hose is coming apart from the inside at the hydro-boost and the piece of hose stuck in the orifice is causing the noise. Sometimes, I don't know about Rams, they put some kind of orifice into the heater hose and it causes a noise like this.

Chris

 

Brakes fine, steering okay other than worn box. It does occur with heater/ac off...first thought. I'm sure it happens while under load I just can't hear it as well but it doesn't change speed/volume/tone. It's like a 1-2 second whir that fades for a second then increases in volume over and over. I popped the hood yesterday it seems to be at the front of engine, but the fan noise overwhelms it. Seems more pronounced after warm up.

 

Get a piece of tubing and put it in your ear, move the other one around the engine bay. It might help you isolate it a little.

Watch out for that fan!

 

Have you watched your A/C compressor clutch while this noise is occurring, to verify that it is staying disengaged the whole time? Maybe something is acting up in the HVAC, causing it to keep cycling, even with the switch off.

 

I'll check it out, I'm also going to go back and check the steering box, I drive the truck so infrequently that I didn't notice that I have a delay in steering. I can turn the wheel an inch or so and it takes a good second for the tires/linkage to react. If you are making a true turn it's not noticeable other than just a loose-wander feel.