Got an odd sound coming from my 5.9l Gen 1. Don't know what it is, but it's throttle responsive. It doesn't do it all the time, but when it does, it is when the engine is pulling hard, and fades away. then goes away at idle, or coasting under power or not. Can someone identify it??
Thanks ahead of time.
<iframe width="560" height="315" src="https://www.youtube.com/embed/U4aRM3cxBWw" frameborder="0" allowfullscreen></iframe>