How do you know when you have an exhaust leak...? I know in a gasser you can here the ticking noise but my truck is so loud already I don't have a clue on what to listen for.

 

Probably not so much listening but looking around the manifolds and up-pipes for soot. You will have to crawl under with a flashlight and look to see it. This will also cause a lack of power and fuel economy will go down.

 

Yep, it's like tracking down any other beast - you're on safari for s**t, the beast's sign that it was here. You see, s**t is the waste matter that is secreted from any well-fed animal: They can't avoid depositing s**t, and it leaves a nice obvious trail where they have been. Now... if the beast has escaped the pen (up pipes, collector, turbo, exhaust manifold) there will be a trail of s**t leading all the way back to where the beast was let out. Touching it will readily leave a dark smudge on your hand, so don't touch anything with s**ty hands... it geats everywhere.

 

Great analogy/metaphor

To the OP... The main area you will want to check is up by the up-pipe collector going into the turbo. If there is soot on the up-pipes, the donuts have failed and are leaking. You can either replace the donuts, or do the permanent fix and buy bellowed up-pipes.