Have you recently taken your turbo off?

 

yeah to do the egr delete

 

Start the truck and open the hood. You should be able to pinpoint where it's hissing. My guess is the up-pipes where they connect to the turbo. It's the same place I had issues. What a lot of guys end up having to do is undoing the connection of the manifolds to the up-pipes, then connecting the up-pipes to the turbo, then reconnecting the up-pipes to the manifolds.

 

this is what i was getting at with my question! What i did was loosened to the clamp back up and got the ypipe and turbo close enough to get the vband clamp around em and i tightented it a little bit and used a pry bar to move the y pipe and then tightened up the clamp some more and moved the y pipe again and this pulled the two pieces together perfectly. But everyone finds their own way to do it. let us know what happens

 

Actually when we did this install it was on a buddies truck and we used kind of the same method you did. We used a .... large.... "persuasion bar" and a BFH to get it in place. Not what I would do on my own truck, and certainly didn't want to recommend it to the OP haha. It did work though...