AZjeff
$50 Site Donor 2023
Was under the '16 Silverado today looking for a small rattle and came across this thing in the exhaust pipe just after the muffler. Called an adaptive valve, it's a spring loaded weighted flapper who's job is to attenuate exhaust noise to eliminate the annoying low frequencies. Apparently they can also fail causing an annoying rattle and also in rust areas they can get stuck shut. Exhausts last forever here so I'd have to intentionally eliminate it. Sounds like an answer looking for a problem, thanks GM. At least it's not computer controlled voodoo magic.
Video from company that makes them:
Video from company that makes them: