Strange and Annoying Engine Noise - Help!

Hello everyone - I am having trouble identifying the engine noise in my 2005 DC Tundra 4.7. It started a few years ago and at that time it was very minor and now it's becoming more constant. The best description I can give is that it sounds like and owl living in the engine bay. It's more of a whooing than a screeching belt sound. Below is a video of the sound:

https://photos.app.goo.gl/68jT7VNRSvCThkDo8

It's very constant in the video. It used to be very infrequent and quieter. You can't really hear it outside the truck. Thoughts? The serpentine belt is fairly new and looks good....

Thanks for any diagnosis.

 

Sounds like your fan clutch, but you can hear that from the outside too.

 

Thanks bmf4069. Something I need to check for sure. It's hard to hear the noise with the engine running, but I'll bet it's there. The video didn't pick it up, but, sometimes there is no sound at all for miles and then it comes back. Lately it's been more constant. Early on it truly sounded like an owl in the engine bay wooing at me. Next I'm going to check alternator/ps pump/water pump/idler bearings/etc. for any kind of bearing play. However, I don't think that kind of sound would come from a bad bearing. Also, it's not always rpm dependent. Meaning that sometimes the noise goes away with rpms, sometimes it's still there, and sometimes it changes pitch with the rpms.

 

Maybe bearings, probably a bushing. Loosen the belt, give everything a spin.

does it come or go when the a/c clutch engages?

 

Reminds me of a vacuum leak.

 

Thank Mr. Bee, I'll be checking. No, it's there regardless of the A/C clutch engaging.

 

That's a good thought... Wouldn't that lead to a CE code?

 

I don't know, but the sound has that quality to me. Sorry I'm not more help.

 

Did you check the idler pulley?, that's what I would check next. Good luck.

 

If you’re able to remove the drive belt, then do so and start the engine, that will eliminate any of the rotating accessories

 

Hard to tell if it's inside the cab or not, I suspect it's in the engine bay. Do us a favor, check if it's louder in the driver floorboard, near where the steering shaft goes thru the firewall. Your steering shaft seal may be deteriorated, making you hear what's in the engine bay, and if it's louder by the brake pedal, we know where to be looking, and it's not inside the cab.

If it's not louder in that area, does this happen when the air/blower is off? With heat on at half-blast? With A/C on at half-blast?

Personally, it takes 2mins to loosen serpentine belt, then you can rotate all the pulleys by hand. This sounds like a bearing fail, and you probably have a pulley that's shot.