I’ve been using our long-term 2023 Toyota Sienna as a moving vehicle over the past few weeks, so I’m getting rather familiar with the cargo area and how things work. Its cavernous amount of space is of course delightful, but I have one particular bone to pick with the third-row seats.
For whatever reason, the third row in the Sienna doesn’t lock into a down position. It uses gravity to keep it in place once you’ve “stowed” it. I’ve been driving around with that third row down most of the time, and when you go over bumps or large heaves, the seats will literally hop up and down. You can hear the sections of seat moving around, and I’ve even caught the “40” portion of the 40/60 split fold moving high enough to see it in the rearview mirror. This smaller portion of the third row is considerably lighter, which is presumably what is allowing it to move around more. A number of complaints for the same thing can be found on the NHTSA’s official complaint section. Some of those folks claim the seats fully extended into the up position due to being jostled about, and while that hasn’t happened to me yet, it sure is disconcerting to see and hear them bouncing around back there.
You can solve this problem by either putting enough weight on the third row in cargo items or by just putting the third row up for everyday usage. But that just shouldn’t be the case, because the third row should lock into a down position such that you need to pull a latch or something of the sort to unlock it.
The actual loading and unloading process of the van is hindered by the moving seats, too. Since they’re just sort of floating in place, they bob up and down as you shove items on top and over them (particularly the smaller 40 section of the row), creating a floor that is anything but flat. It’s particularly annoying when you’re trying to pull a heavy item from deeper inside the cargo area out of the van, as you first need to lift it over the leading edge of the bobbing seat, and then it will naturally slide out. A locking mechanism to keep these seats in place would solve all these problems, so we’d love to see that in a refresh for the Sienna down the road.