2013 Crewmax 4.6L TSS - slight vibration/noise shifting out of OD

I've owned this Tundra for less than a year and it has just over 142k miles. It runs great and hasn't given me any significant trouble. I recently made a long trip (450 miles) and noticed that each time it comes out of overdrive (or whatever you choose to call the highest gear lock-up), it has a very slight vibration/noise that feels like you just drove over 3-4 minor grooves in the road with the rear axle. For a long time I actually thought it was road/pavement noise. Then I started to watch the pavement more closely as well as the Tach. Every time I could feel the vibration, it was just shifting out of the highest gear/lock-up. It isn't directly related to specific speed, but definitely related to the initial down shift to grab more RPM. Any thoughts?

 

After some additional searching on the forums (funny the best search term was "rumble strip"), I'm beginning to believe this may be the infamous Toyota Torque Converter failure.
see post #57 (https://www.tundras.com/threads/issue-possible-transmission.9750/page-2#post-2042137)

I plan to reach out to my local transmission guy and see what he knows about the issue (and the cost).