I have a 1999 F350 with the Powerstroke. At 2100 rpms it makes a very loud howling like the secondaries opening on a Holley 4 barrel carburetor. It doesn't matter if it's under load at that rpm or just maintaining speed. It occurs in all gears and in park. I have a friend with an identical 2000 F350 that doesn't make any induction type of noise.

Anyone have any idea what's causing it? It can't be normal. It's intollerable at 2100 rpm which with my 4:10's is right about 63 mph.

 

Do you have an aftermarket intake on it or any other mods, or is it all stock??

 

It is all stock. Even the stock air filter in the original housing.

 

Are you sure it is in the air induction. We just had a psd do the same thing (howl) it didn't happen until rpms were around 2200 a week later the turbo locked up tight. Not saying it is the same problem just giving you a personal experience with that noise.

 

I don't have any idea what it is, it just sounds like a bunch of air rushing in. The truck only has 51K so I hope the turbo doesn't go yet!