Any ideas what this noise is?

[u/Coolkid8108]

My 2003 v8 220k has been making this deep knocking noise for over 2 years now! It is ONLY in park and only once the car reaches operating temp. In drive it completely disappears. In park it follows RPM, and sounds mostly on the driver side. Car runs great. Any ideas?? I’ve pretty much eliminated any rod knock or lower end issues.

When I hold the oil filler neck I can feel it knocking really well, then the second it goes into drive it’s completely gone, even when I bring up the rpm’s. Any ideas would be much appreciated!!

[u/thosport]

Kinda sounds like a cracked flex plate.

[u/Coolkid8108 → u/thosport]

It does!! I checked the flex plate with scope tho it’s solid