My friend has an 05 f150 5.4 and has ran it for who knows how long with out oil. It knocks for about 10 seconds on startup then stops. Any ideas of what it could be. I thought it was rod knock but i havent seen it go away after a certain time. It may be though. Any help is good

 

What do you mean without oil ? It holds 7 quarts. He ran it empty ? Where did all his oil go ?

 

WHAT? Ouch! Buy a bicycle it doesn't require oil or very much BASIC maintenance.

 

It had a leak that he kept ignoring and we put 5 quarts in it

 

my guess is a bearing or lifter tap. do a compression test and see if it still is healthy enough to run. this is why some people don't deserve nice things....

 

What stops? The engine or the knock?

 

The knocking stops ans runs just fine until he shuts it off then knocks when it starts back up

 

Only diagnosis have is your friend is a dumb ***.
As for the knock, can't help.

 

Anyone thinking timing chain rattle?

 

Can you post a video for us to hear?