1st and 2nd gen Sequoia and LC since the 80 series had a true center diff (i.e. gears like front or rear diff), so you could run 4hi or even 4lo on dry pavement with the center diff unlock. And I thought 4th gen 4runner and Limited trim 5th gen 4runner also uses a true center diff. Other 5th gen 4runner uses a part-time system with no center diff. I have a 2nd gen Sequoia and the ability to back my heavy trailer up my steep driveway in 4lo with center diff unlock is awesome. It takes a lot stress off the transmission in 4lo. Most crossover and even trucks that have 4auto uses clutches instead of a true center diff between the front and rear axles. The problem with clutches is wear and heat. I.e., clutches wears out over time and slipping clutches generate heat. This new Sequoia is like the rest of Toyota's trucks now (Tundra and Tacoma), where it does not have a center diff at all. There is no differentiation of speed between the front and rear axle so it can bind up on dry pavement if making turns. Basically the front and rear axles are locked together like a spool. There's pros and cons to the different types of 4wd systems. The pros of this part time system that Toyota uses for the new Sequoia and their pickups is that it is more robust and less parts to wear out and break. Cons are that it can't be used on dry pavement. The front and rear axles needs to be able to slip so that the driveline doesn't bind up.