For the older, our 2005 Sienna needs a timing belt every 90,000, it's the same 3.3 engine that's in the older Highlander, our friends have a 2004. He has somewhere in the neighborhood of 300,000 miles and our Sienna recently turn over 200,000 miles. The newer Highlanders with the bigger engine have timing chains, our 2007 Tundra has chains on the 5.7 engine, I've heard chains are life time, the Tundra has over 270,000 and runs like new. I don't know how the used car costs are around where everyone else lives but around here they are sky high, we've had a few letters from the dealer asking if we wanted to sell our used vehicles. I have heard that some people are having issues with CVT transmissions, actually a lot of the newer vehicles have throw-away transmissions, I've had some friends mention that when they needed to get some work on those transmissions, they were told by transmission shops that they wouldn't work on them.