Rattling while iddling

[papashago]

i have a 2008 F350 with a 6.4l got it a few months back and it has been great i really like the truck so far but last week it start rattling while iddling its pretty loud when cold. but goes away when the truck warms up and can only hear it when you first fire up the truck weather its warm or cold then it goes away..... The truck drives like new and i cant tell what it is. this is my first ford and my first thread on this forum. any advise would be great thanks.

[Shinny]

It sounds like the idler pulley. There was a TSB for that a couple years ago. Mine did it to, the replaced the pulley and no problems since