I'm wondering if any experts out there can tell me why this sounds so horrible.

 

Sounds like the serpentine belt.

 

The belt looks OK and it sounds like it is coming more from the other side. Would any transmission problems create more noise while in park? Here is a list of current fault codes. Any idea what all could cause the incorrect gear ratio in all gears?

P0456 - Powertrain
Evaporative Emission Control System Leak Detected (very small leak)
P0700 - Powertrain
Transmission Control System (MIL Request)
P0731 - Powertrain
Gear 1 Incorrect Ratio
P0732 - Powertrain
Gear 2 Incorrect Ratio
P0733 - Powertrain
Gear 3 Incorrect Ratio
P0734 - Powertrain
Gear 4 Incorrect Ratio

 

There are a bunch of things that could make the noise. Not being there, it's a little hard to tell where it is exactly. Get yourself a wooden dowel rod about 2 or 3 feet long.Put your knuckle on one end and use that knuckle to press the cartilage flap on your ear closed. Press the other end on different parts of the engine. It will act just like a stethoscope.

To my elderly ears, it sounds like a shield of some sort rubbing or possibly your starter drive not letting loose completely.. Try using a piece of 2X4 on the starter and give it a decent whack (<--------Fancy technical term) with a DBH. (Darn Big Hammer, about 2 pounds.)

 

I ended up changing the speed sensors since they were only $16. I jacked it up and used a stethoscope to poke around and the high pitch grinding wheel type noise was coming from the transmission. I'm not sure the last time that the person changed it but I changed it and put a new filter on and some Lucas Transmission Fix in it. So far so good. That horrible noise is gone and no errors have come back after running some errands.