i figured out where it is coming from. it is not the vac pump. it is coming from the fuel bowl, or right near there. any ideas why there would be a loud wine/ squeal noise coming from there when you turn the key and goes away after about 20 30 seconds. is starting to do this more often than not i would like to have one week where something does not go wrong with this truck

 

Just a matter of time friend. Gradually you'll get everything working and there will be nothing left to fix and you'll be our forum expert :-P

Anyhow, near the fuel bowl huh? Does it do it when cranking or only when you turn the key on without the engine running.

Could it be the Glow Plug relay? Try unplugging it and see if it goes away. If you think it is the fuel bowl have you pulled the fuel filter, checked for debris and cleaned it out? Try unplugging the fuel bowl heater and see if the squeal stops then.

These are just ideas and a place to start. If nothing else here's a bump.....

 

only does it when you turn the key on and then a couple seconds after the truck starts and does not come back until you start the truck again. it does not sound like a realy chattering. but i could be wrong. it is hard to tell for the reason it does not do it all the time.