How much is it to buy a replacement Blender Gear for my 1998 Ford Expedition? on 1998 Ford Expedition

Would I be able to fix this problem myself if I could purchase a new Blender Gear because my A/C only blows hot air and will not change to Cold air. I read that there is a product called The "HeaterTreater", does anyone know if that works? And I have also been told I can go through my glove box and locate the Blender Gear box and change it to hot or cold that way, is that true?

1 answer 2 comments
It's not pronounced that way in my manuals; If your talking about the blend/temp door actuator then maybe you can get the right part. In a pickup it is at the bottom of the heater case at the hump in the floor.
Thank you for your reply but that was what a local mechanic had explained it to me, so that is why I had labeled it a Blender Gear. So I think what you labeled it maybe it.
Thank you for your help.
They're about $60.00 at the parts store.