Idle clatter sounds different every time

[HookMeUp]

The idle clatter sounds different every time I drive this truck. Sounds louder, has more a tinnier noise, a quiet rattle. It just doesn't sound the same every time I drive it. Is it me or is this the nature of the newer trucks?

 

[EDankievitch]

Yes it is. on these new truck the computer changes the timing as it runs and when it goes into the re-gen cycle.