Squeeling from engine compartment

[Arnoldthepig]

Does anyone else have a squeeling / squeeking sound from the engine compartment when the motor is turned off. It keeps making this sound over and over when the motor is off and has done it since day one. I can't really pinpoint where its coming from. At first I thought it was the wind blowing through the grill but thats definitely not the case...

[cmpcpro]

Is it your electric fan? Maybe the bearings are going or something?

[Arnoldthepig]

It can't be anything thats moving because the engine is off....sounds almost like pressure releasing but I just can't pinpoint from where...it almost sounds like a faint steam engine whistle....

[pm26]

Truck blowing off steam?

[Arnoldthepig]

Hahah it could be! Everthing else for the most part seems ok, I can't find anyone else whos truck does this. Today I had it parked for 4 hours, It did it from the time I shut it off until the time I restarted it. No engine lights tho so I will just make a GM diagnosis on my own, "its normal"....

[ShotgunZ71]

Maybe the mice are tired...

[Arnoldthepig]

Hahah it could be! Everthing else for the most part seems ok, I can't find anyone else whos truck does this. Today I had it parked for 4 hours, It did it from the time I shut it off until the time I restarted it. No engine lights tho so I will just make a GM diagnosis on my own, "its normal"....

[Arnoldthepig]

I took the truck into the dealer today for a few things. One being this sound under the hood. I spoke directly to a tech who said the noise usually will happen 4 hours after the vehicle is turned off due to the a/c system purging out the moisture in the hvac system...he said it helps to keep the musty smell out of your hvac system...I have never heard of such a thing has anyone else?

[Arnoldthepig]

I just remembered what the tech told me about this feature I described above...Its called "afterblow" to dry up any condensation in the HVAC system to avoid the musty smell when turning on the HVAC after the vehicle has been sitting. Apparently this is the noise I was hearing...

[20L8TSierra24]

Mine has one "squeak" going from v4 to v8 mode occasionally. Very faint though. I was looking for it after I saw this thread.