2013 Tacoma. Rattling noise when accelerating from coasting

I’ve read quite a few threads about a “ metallic “ type rattling that occurs when accelerating from a coasting. Mine does not make the rattle noise from dead stop accelerating, only from accelerating from coasting speed.

I have had the heat shield checked and transmission inspected with no diagnosis and after reading other threads it sounds like others have had “ no diagnosis “ or “unable to replicate “.
It doesn’t quite seem like an engine ping/lower octane type of ping but I am going to try some high octane.

The ping does not occur at cold start and low rpm / speeds. It always occurs under load when accelerating from a coast.

It does not appear to be getting worse but I can’t quite figure it out and looking to see what others have had as far as diagnosis before I bring it in to Dealer.

Thanks in advance for any additional input or info!

 

Specs of truck, including mileage and how it's used could be helpful

 

2013 Tacoma PreRunner. 83k mileage. V6. Use it for work ( in town/stop and go driving ).
Taking it into Toyota dealer next week.
Have taken it to transmission specialist and they found nothing as it related to transmission.