Hello everyone,

My truck has been deleted since 5k miles, currently at 88k miles (EGR still intact).

I am trying to figure out what is causing my exhaust to whistle so loud.

I am not running the whistle tune (I never liked it).

On start-up, the truck will have the usual hiss it has always had; however, after a couple of minutes, the exhaust begins to whistle and only worsens as the engine comes up to running temp.

This has been going on for about four months (I know, I know, been putting it off).

About a month ago, I replaced the turbo actuator.

I checked around the manifold for signs of soot but saw nothing.

Manifold looks normal from what i can see with the EGR in the way.

The truck builds boost just fine and drives like it always has.

What else should i check?

What could be the problem?