I had to check out the 3.5 eco thread with all of the issue's they're dealing with. Granted most are late model 17's, with the 10 speed.
They have noises galore with the powertrain combo. Transmission and otherwise

Doesn't mean I'm not going to stop researching our clicking/popping... (I can't seem to find a word that accurately describes it).
But after some time in their threads I think we're doing okay.

If you guys have the same off throttle sound and its the same as the 17-18 3.5 and want to replicate it while stationary just put it in drive foot on break and blip the throttle.
my rattle doesnt occur if there isnt load on the engine.

No weird noises with my 2018 5.0 at all from what I can hear.. I'll keep my ears open though.

Do you hear any clunking while slowing for a rolling stop and then accelerating again?? What speeds are you all going when this is happening?

I get a loud clunk or bang every now and then with mine....I look at my wife and ask what the hell was that? That is almost always on a down shift or letting off the gas and coming to a stop sign. I can't seem to find the thread that discusses the TSB for trans module re-flash on trucks that were manufactured prior to Dec. 2017. Mine was Oct 2017. If anyone catches it in another thread I would appreciate it if you could PM me or post it here. I am taking it to the dealer on Thur. and would love to be armed with the TSB number.

I have pops, under load with 5.0, 3.73 gears and 10 speed. Seems most obvious from 6-7 gear in full auto. Also, I've had some hesitation shifting up/down after hard throttle and pulling off suddenly. I'm not sure if this is just me getting used to this tranny/engine combo or something actually wrong here.

Im experiencing the noises described in this thread and will be going to the dealer Soon

Motor Mount ?
 

Motor Mount ?