Let’s play a game: Name That Sound!

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Sounds one of the noises mine is making, not sure what it is. If you open the hood, is it louder from what sounds like the front top of the engine? I will be taking mine in to the dealer this week. Symptoms: not present when cold, reliably occurs when warmed up, very noticeable from outside at idle.

It's the cam phaser going. I heard this knocking before I ever heard the rattle. It will only get louder if not addressed. It sounds like it was coming from the top side of the motor.
A few people on youtube have posted similiar videos:

https://youtu.be/NgmaUhEtU6k

https://youtu.be/oKDUPIHnjC0

 

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Did it get diagnosed?

No rattle on start up, but once warm the engine sounds like a tractor at idle. That’s the only way I can describe it. It’s not super loud, but definitely noticeable at driver side front wheel well and at the front of the truck. Can’t really hear it from passenger side.

Truck is a 2017 with 45k miles. COBB tune since about 15k miles.