Welp, my 1500 5.2L V8 4x4 is my baby..more expensive than a newborn, lol.

So, it's been doing it awhile..but I'm looking to start doing a lot of fixes, tune ups, add-ons this spring and want to do all fixes first.

The sound I'm hearing only happens when I'm accelerating (can barely hear it now since I busted a hole in my muffler..lol)..It's just a flapping sound, like..it sounds like the exhaust on an air compressor (the gas companies use and such), with the metal tab on top that flaps as the exhaust is released, ya know? Not sure how well I'm explaining, but it makes sense to me, lol.

Soo..what could this be? Head-gasket, valve/cylinder, etc?

 

Sounds like a header gasket.

 

Open the hood, rev the engine and locate the source of the sound.

 

Had the same noise drive me nuts for weeks. It ended up being the rubber gasket/seal that goes around the outside of my headlight housing. After replacing headlights, it has always hung out and flapped in the wind..