Dude your engine bay is beautiful lol, but judging from the video it seems to be loudest when you were next to the bell housing.
Also I can confirm that mine does it even when the engine is not on, I killed it in gear and the noise didn't change, other than slowing down along with everything else as expected.
I'll have to do that tomorrow, I'm planning on doing the seafoam smoke test as well so I'll get a video of both.
Today was quite a bit colder than the rest of this week and it seemed to be louder than normal. Idk if this is because I've had seafoam in the crank case the last few days (have hardly driven it) or if it's really temperature related.
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I kinda went down the rabbit hole on engine oil today and some people say they have quieted up their engine noise with Rotella T5/6, it's a diesel engine oil but it has higher levels of ZDDP (Zinc) like the older motor oils had when the 4.0 was being made. Apparently it's really beneficial for the motor, lots of people swear by it. People mostly use it for lifter tick but I'm wondering if it would affect our "tick", wherever it is. I know you guys are due for an oil change soon but if you don't wanna risk it I'm gonna give it a shot and can report back here. Probably won't be for a few weeks though.
This guy explains it better than I can if you have the time to watch: