In short I am sure glad I reported this in April 17 with 31k to the dealer, who at time denied me as TSB only covered up to 15 year models. I had also emailed Toyota corp in 18, which gave me an incident #. As when I found out a week ago the TSB was revised to cover 16 & 17 year models. But by last Friday I rolled over 68k and outside the powertrain warranty.
Service tech went to bat for me and advised I call corp directly, and explain the above (previously identified problem-even though they blamed the tires) waited 2 days and Toyota corp approved covering the fix of new needle bearings, which I believe will have a 1 year warranty. Very thankful not to have to spend my $ on a known issue. But time will tell if new needle bearings in a too sloppy diff will lead to a repeat of the same problem. I do feel the vibes got worse as I racked up more miles as time went by.
I must say I felt the vibration or became aware of it somewhere after 20k, but was only clued there being a TSB and the revised TSB by my fellow T4R members here.
Can we make the TSB Rev 2 a sticky, as I imagine many out there have the same problem.
https://static.nhtsa.gov/odi/tsbs/2018/MC-10142876-9999.pdf