I'm trying to discover if others have similar vibration problems. I think it's a potentially significant wear/failure problem and want to learn more before challenging dealership comment that it's "normal" and " nothing to worry about".

Vibration is subtle - it's only felt on smooth roads, but comes with audible increase in vehicle noise during this 1000 rpm range... a noticeable low frequency howl. And occurs at an rpm that coincides with normal highway driving speeds.

Update from Jan 30, 2022: I raised this with dealership, who first claimed it was "normal". After corresponding directly with Toyota Canada, the dealership was willing to do further investigating. They did a "re & re" on the torque converter and said they fixed it. As soon as I got on the road and into that vibration range I knew they hadn't improved it significantly--if at all--but I was so unimpressed with their fudging that I gave up. Since then, Covid as restricted driving to local only, so seldom on the road and into long distance driving where car would be in that range for lengthy period (lengthy being anything longer than 10 sec), so no significant change.