Tookm my truck to the dealer yesterday to get the trans gasket replaced and they told me its about a week for parts. They gave me a 09 tahoe xfe with the 5.3 and 6 speed tranny. Long story short I missed how quiet it was , my question is, is a exhaust really a benifit. i might take mine off and put factory back on. I have 08 sierra 5.3 with flowmaster 50 series dumped. Anyone that has seen actual numbers on a dyno would help or does a tune benifit from a exhaust