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Second-Gen Sequoia: Leveraging The Tundra (Or Vice-Versa)

It’s been a while—since model year 2001—between Sequoias. But with the Tundra out, the vehicle with which is shares lots of technical genetic material is now rolling, too.

“At the first engineering development meeting with the entire team, I announced that our goal was to create a vehicle capable of delivering top-level comfort, quiet and convenience, and effortless functionality over a long distance.” That’s Motoharu Araya of Toyota Motor Corp. Given those parameters—comfort, quietness, convenience, effortless functionality, and the ability to drive it over a long distance (he also speaks of the “1,000-mile-a-day concept”)—one might think that he’s the chief engineer on a, say, Lexus car program. Which is not the case. Rather, he was the chief engineer for the 2008 Sequoia full-size SUV.

Full-size is something that he’s familiar with. He’s worked on the Sienna minivan. The Tundra pickup. And the previous Sequoia (which was introduced in 2000, and had minor changes in MY ’05, which just goes to show that not all programs are done on a three- or four-year cycle). As is characteristic of Toyota chief engineers, it isn’t a matter of simply spending time in meetings in offices and occasionally out on the roads. Araya was not the chief engineer on the Sienna. Yuji Yokoya was. One of the claims to fame of the development of that vehicle was that the chief engineer had 53,000 miles of seat time in minivans (Toyotas and other makes) in order to better understand what was needed. Araya recalls, “I was often the person riding shotgun and taking notes and taking my turn at the wheel mile after mile after mile.” In addition to which he’s logged more miles by pickup, van and, importantly, SUV. One consequence: “I get it. I get the size thing. I get the power thing. I get the cupholder thing. I get the secure-feeling thing. And I get the comfort thing. I am, I admit, a big car guy.”

 

He evidently gets it.

About the 1,000 miles. This is actually something of a rule of thumb for Araya. He calculates that it is “within the limits of how many American ‘road warriors” attack long-distance driving.” He reckons it is about 14 hours on the interstate. Which is why he focused his engineering team on those aforementioned parameters. And he believes that even those Americans who aren’t quite as zealous as those who grip the steering wheel and don’t want to give it up are looking for capacity, comfort and conveniences like entertainment when they’re out on family vacation. Which pretty much means, in a word, “bigger.” 

Bigger as in the 122-in. wheelbase, which is 3.9 in. more than the previous, and an overall length of 205.1 in., which adds 1.2 in. The width has been bumped an inch to 79.9 in., and the height is 74.6 in., up 0.6 in. And what’s bigger on the outside is bigger on the inside, as well, for the SUV that offers three rows. Although the third row in the Sequoia is, like most third rows in SUVs, not exactly spacious, one of the things that they did in developing the vehicle was to develop an all-new independent double-wishbone rear suspension (the first for a Toyota SUV) with coil springs that are positioned outside the boxed frame rails: in addition to serving its appropriate functions, the rear suspension also contributes to an improvement in third-row leg room and cargo capacity.

Speaking of the frame, it should be noted that compared to the previous model, its gotten beefier, as well. The rails are fully boxed high-strength steel. The frame rail cross section is thicker and the wall thickness is increased. Torsional rigidity is 20% better, flexural rigidity is 70% better, and lateral rigidity has been improved by 30% compared with the ’07 model.

One thing that is fairly obvious about the ’08 Sequoia is that it resembles, in no small way, the ’07 Tundra. This is more than a mere familial relationship, where one vehicle establishes a “look” and subsequent vehicles follow. The two vehicles were in development together. In fact, according to Araya, “The Tundra and the Sequoia concepts were proposed to top management and accepted during the same meeting.” The two vehicles were developed in parallel. Araya describes the vehicles’ development processes as “a dual project joined at the hip,” and says that his role “was to simultaneously develop the chassis, drivetrain and powertrain for both the Tundra and Sequoia and oversee the upper body development of the Sequoia.”

In effect, this is a case of being separated—not entirely—at birth, as not only is the Sequoia manufactured (exclusively) at Toyota Motor Manufacturing, Indiana, in Princeton, but the Tundra is built there, as well (though in limited numbers compared with the dedicated plant in San Antonio). Araya admits that in some ways the Tundra has benefitted from being paired during development with the Sequoia. For example, he says that because an SUV is heavier than a comparably sized pickup, the systems and components have to be somewhat beefier, so factors from powertrain calibrations to suspension components were designed for both to deal with the requirements of the SUV. However, the Sequoia benefits from the Tundra, too: the two vehicles are identical to the B-pillar.