Diagnose this sound (1 Viewer)

[troutbum]

This has only occurred for two days and I want to nip it in the butt before anything else happens. I get this sound when I come down off the throttle from about 1500 rpms. I'm not sure how to describe the sound, (I wouldn't do too well on Car Talk haha) but here is a link to the video from this evening. I'm at 299k miles with regular maintenance.

Link to the video:
20161019_181349.mp4

Thanks for all ideas. Hopefully y'all can help.

 

[half k cruiser]

Maybe bad video but I don't hear anything out of the ordinary for a 1FZ

 

[troutbum]

Maybe bad video but I don't hear anything out of the ordinary for a 1FZ

It is a hard to tell but that's the best I could get. The first and second rev when it comes down is the best sound. I'm wondering if maybe there is a leak in the system.

 

[BILT4ME]

Pretty sure it's the putter....putter....putter.... sound at the end of the rev.

That sounds to me like a crack in the wye pipe on the exhaust. When the truck is cold, start it up and place your hand between the two halves of the wye and feel for exhaust puffs. Has to be quick cause it gets hot quick. You can also use a piece of vacuum hose and pass the one end between the wye and the other end in your ear to hear it.