2015 5.3 exhaust leak?

[Tyler69]

Hello, 

purchased a 2015, 1500 5.3 a few weeks ago and last night on a very quiet road as i was accelerating i could hear a click/rattle in the exhaust. After driving it a little bit more today with the radio down and AC off i can definitely hear it more. It doesn’t really do it when i have the cruise set but as soon as i touch the throttle to accelerate i can hear it start. I’ve done some reading and some people say it’s the Flap valve in the exhaust but I’m not sure. AFM is disabled via a programmer. Any thoughts? 

Edited July 5, 2021 by Tyler69

[Tyler69]

[CamGTP]

Tie open the flapper to rule it out.

[rlcole321]

Sometimes the material in the cat's come apart and you can here them rattle, eventually they will rattle enough, come apart inside and restrict the flow.

[CrawlSlow]

Connect a smoker to the end tip and see if there's any smoke coming out from your exhaust system.

[Hawaiian Brokechanic]

On 7/5/2021 at 12:49 PM, Tyler69 said:

Hello, 

purchased a 2015, 1500 5.3 a few weeks ago and last night on a very quiet road as i was accelerating i could hear a click/rattle in the exhaust. After driving it a little bit more today with the radio down and AC off i can definitely hear it more. It doesn’t really do it when i have the cruise set but as soon as i touch the throttle to accelerate i can hear it start. I’ve done some reading and some people say it’s the Flap valve in the exhaust but I’m not sure. AFM is disabled via a programmer. Any thoughts? 

Did you get it figured out?