[OldScoolCamaro]

Clutch "chatter" is normally associated with pulse/vibration in conjunction with noise. I think you mean just noise. There is nothing quiet about the mechanical operation of the ZL1 it's S/C, transmission, and driveline. Everything at times makes varying levels of noise. At idle you may hear noise coming from the transmission area from inside and outside. Inside the car you may hear noise coming from the area of the transmission tunnel. It can be at one time or another in any area of operation from shifting, to driving in gear, or sitting in neutral. Also the rear axles, carrier/rear axle housing talk alot. If the noise is at the same relative level as any other mechanical sound(s) of operation and does not get higher or more pronounced over time then it's what's baked in the cake. The HD stuff tends to act that way.