Hi, I have a very loud, can be heard from the inside and out side grinding sound. It happens when it wants. Can't makes it happen and doesn't do it all the time.
When inside the car one would think it was coming from the blower fan or maybe the plastic gears that open and close the heat/ac channeling vent doors. (Inside the duct work) sound like it's coming from the passenger side dash floor area.
When outside the car you would think the transmission, diff. or idk was grinding.
It's so loud that you would have difficulty ordering from a drive throu. sounds like it's under the passenger compartment. not the engine area, more central to the vehicle front to back...

It's a hard sound to describe I have never actually heard a vehicle make this sound before.
Pretty sure it's not plastic gears in the heat/ac unit. Leaning more towards diff. Or a 4 wheel interlocking or engaging issue?

Any ideas would be greatly appreciated.
Thanks

 

So, if it's making this sound while sitting at a drive through, then why don't you get out and walk around it, look up underneath it, etc while it's making this sound to determine the exact location it is coming from? You have the car with you, so you have to do a little bit of researching on your own.

 

If you are stationary then it rules out wheel bearings/cv joints.
Could be the over run clutches (alternator) these give out after a time
and can be loud.

 

Jkeating: yeah, I said it's loud enough to cause difficulty ordering at a drive throu. So someone reading this post would have an idea of the volume the noise is making. If I could narrow down where the sound is coming from when i am under the vehicle then I wouldn't need help. I would be able to fix the issue.
How ever thank you so much for your help anyway.

Bigtsr: it does make the noise when stationary as well as moving. So yes I agree.
I am hard pressed to believe the sound is that far forward tho. When the hood is up I hear the noise more from under the car like standing by the drivers door kinda thing. Not in the engine compartment. Also it seem to stop making the noise in park. But coasting in neutral has no effect sound will continue?
Your input is appreciated
Thank you