I’ve experienced the holy grails of exhaust rattles.
My 2016 v6 got both the
AFM spring valves rattle and the
resonator rattle. I replaced the resonator with a Jones X-Pipe I bought for $35 and shop installed for $100. Replaced the exhaust from the AFM valves to tips with a ZL1 stock NPP exhaust (from a manual so no AFM valves).
My 2022 SS had loose heat shield rattle which the dealership said they tightened the shields. Then also got the NPP valve squeak, I didn’t ask what they did but they fixed it. I keep the exhaust in Track 24/7 and on the v6 it was unplugged so the valves were always open