When I picked up a couple sacks of portland cement they offered to put it in my truck. They were a little embarrased when the truck turned out to be a Highlander, but the weight was not a problem. It is definitely not a truck, and not really a station wagon either. It is also not an off-road vehicle, although it does quite well on rough terrain if the rocks aren't too big.
The Toyota Highlander is built on the Toyota Tundra frame and uses the same running gear. However, at best the Tundra is a 7/8 scale truck, so it's not all that great. What you have is a truck or truck-based SUV.
If you had an RX330, you'd have a car-based SUV.