Interesting Rattling Noise

Good afternoon all,

I have a noise that just started happening on my 08. Almost sounds like a diesel. The noise only seems to happen at engine brake, in between shifts, or when the trucks speed has "matched the engine rev" so to speak. Like it doesn't happen when accelerating but once you maintain steady throttle, the noise will happen at RPMS under 2.5K. Below are some videos from the noise when engine braking then at steady throttle first gear at around 2k rpm.

Any have any ideas?

 

I am not a manual guy, but was in my younger car days, that sound like a throw out bearing and or clutch