Pretty consistent after 1900, with power under load, if I let of the gas it will go away and immediately come back when back on the gas

 

These are a pain to find. Absent suggestions from anyone else, I'd start by taking the serpentine belt off and looking at everything connected to it. If the water pump is leaking, at all, through the weep hole, or is just old enough to perhaps warrant replacement, you may just start there. Check for any play or grinding in the alternator and idler pulley, too.

Mark

 

Any progress on this?
My truck was doing the same thing and removing the belt didn't quiet anything down. Tightened up the exhaust flanges and turbo connector to Y pipe. It quieted down slightly but would still make that horrible sound above 1900 rpms.

Last Saturday I hauled my 5th wheel over the mountains to Pahrump Nevada. On the way there we were traveling some wavy road service and the sound suddenly went away. It came back and then went away again. I told my wife that it must be an exhaust leak and the rough road is causing enough movement to silence it.

A few miles more and the sound changed dramatically. It was as though a piece of an exhaust gasket blew out and squealing chirping sound ceased. We could hear the exhaust leak but it was much more tolerable than that high pitched squealing.

My plan now is to order some new exhaust manifold and connector gaskets and tear into it.

 

Sounds about right , I had figured mine was an exhaust leak as well but no time to fix at the moment, was pulling a bobcat and implements on my gooseneck and my sound is gone now as well. Will soon be inspecting for soot spots

 

Reading through the Tech Folder it seems there are no exhaust manifold gaskets. Aftermarket gaskets are available but Ford had things metal to metal.

If that is the case, I wonder if resurfacing the head and manifold contact areas is what needs to be done?

 

You can clean them up , ford does offer a gasket set for them and I believe its for this exact reason. Ive worked on alot of 7.3ls and I have always tightened the manifolds up, especially on driver side rear they come loose fairly often. Mine comes in at 1900 rpm as well and continues through the power band and even on the declaration but as of late since I hauled that equipment it seemed to have stopped. I know there is an issue but man is it nice to not have the sound anymore and have everybody call me insane. It might look like a big job but its seems pretty easy for the most part.

 

Order the gaskets, bolts and some other items from RiffRaff today.
Now to find time to do the work.

 

Finished the install of the exhaust manifold gaskets (Ford parts) and the difference is incredible. No more high pitched chirping sounds, whining noises or exhaust leaks and we can actually carry on a conversation while traveling down the road without raising our voices.