LS3 in a 69 Camaro, weird shuttering when turning off engine

[69camarokid]

Hi Friends!

I have a 69 Camaro with an LS376-495 (Ls3 with a GM hotcam) it has about 3k miles on it. For some reason whenever I shut off the engine there is a really weir shaky/shuttering noise/vibration that lasts about a second whenever the engine is shut off. I have not seen any negative problems arise from it, but it is a bit disconcerting and I have no idea why it is happening. Anyone have any ideas as to what is causing this/why and how I can fix it if necassary?

Thanks!


https://www.youtube.com/watch?v=5CnuTcJaMKo&feature=youtu.be

[Gmachine1911]

I’d check to make sure you don’t have a header/exhaust pipe touching the frame/trans cross member and rattling when you shut it off. Same could be true for anything in the trans tunnel area

[blitzer454]

maybe wrong pilot bearing which causes the transmission shaft to push on the crank shaft???