2014 Toyota Highlander: Improvement Through Engineering
QDR (Quality, Durability, Reliability) isn’t enough to keep Toyota competitive. The cornerstones of the brand’s rock-solid image with customers keep it a contender, but are not enough protection against the seduction of competitors with prettier sheetmetal, more technology, and better driving dynamics. Takashi Goto, Highlander Deputy Chief Engineer since 2010, discovered that when he was Drivetrain Manager for Toyota’s Sienna minivan. Stationed at the Toyota Technical Center in Ann Arbor, MI, Goto and his family spent many days traveling across North America on vacation.
“The Sienna taught me the importance of having plenty of space, even if you ended up not using half the things you packed,” says Goto. But the North American buyer showed him the importance of “heroes.” According to Goto: “There are lots of ‘heroes’ in the mid-size SUV segment, and the second-generation Highlander didn’t have the looks or [perceived] luxury. The third generation needed a prominent, outstanding presence; luxury NVH levels; more dynamic handling, and greater ride comfort to be competitive.”
Like the current Camry, the latest Highlander is a major re-do of the existing platform, not a clean-sheet execution. It’s also a vehicle wherein U.S. thinking is taking more of a lead as engineering and product development control for the model shifts away from Japan. All 2014 Highlanders will be sourced from Toyota’s Princeton, IN, plant.
Though the new model is 2.8-in. longer and 0.8-in. wider than the 2013 Highlander, passenger volume is 0.8 ft3 less, and total cargo volume drops by a surprising 8.2 ft3. A quick look at the numbers shows a slight increase in the leg room of the first and second rows (the third row loses 2.2 in.), greater hip room, and 3.5 ft3 more cargo room behind the third row seats. This reallocation isn’t as radical as it might seem as the 2014 Highlander feels roomier, airier, and much more luxurious. Ingress to the second and third rows is easier and, while Toyota says the new Highlander can seat eight, more impressive is that six adults can fit reasonably comfortably.
Even without a decibel meter to measure the difference, it’s easy to discern that the 2014 Highlander is quite a bit quieter than its predecessor. Goto’s engineering team made the dash silencer larger and overlapped it with the floor silencer, added sound insulation to the instrument panel, increased floor silencer and insulator coverage by 30%, adopted spray–on sound insulation for the underbody to reduce both weight and noise, added sound-absorbing tibia pads, augmented the dampening performance of the carpeting, increased the thickness of the side and rear-quarter glass, and changed to acoustic glass for the windshield. They also increased the amount of foam used in the rear quarter panels, door openings, and roof header, while improving airflow around the vehicle to reduce both drag and wind noise.
Handling dynamics and ride comfort were not strong points of the previous Highlander. However, Goto insists that “paying attention to details” brought surprising gains. These include altering the spring curve by retuning the coil springs of the front MacPherson struts, and using low-friction materials in the front dampers to reduce “stiction” under cornering and braking. In back, the previous dual-link/MacPherson strut rear suspension has been replaced by a double-wishbone design with better camber control. And though it can feel a bit stiff-kneed on bumpy surfaces when the vehicle is unladen, its greatest attribute is the cargo space it liberates by locating the coil springs and dampers outboard. The electric power steering, on the other hand, has less friction and a greater heft at speed, giving the 2014 Highlander a more confident feel from the helm.
As before, a 2.7-liter inline four mated to a six-speed automatic transmission powers the base front-drive model; all others are powered by a 3.5-liter V6/six-speed automatic combination. This gives the V6 one more gear than before, and raises fuel economy across the board. The V6 is almost as fuel efficient as the four, due in large part to the numerical increase in the final drive ratio from 3.478:1 to 4.154:1. Other improvements include use of an “ultra-flat” torque converter with low-speed lock up, the addition of sequential shift and snow modes, and an expanded flex-lock range. In addition, neutral control releases the clutch halfway to separate the engine from the transmission when the vehicle is stopped in Drive with the air conditioning off. In practice, the six-speed shifts more cleanly, is more responsive, and reduces engine rpms.
The full-time all-wheel drive system has been ditched in favor of an on-demand system. As expected, front/rear torque distribution varies from 100:0 to 50:50. In high-grip situations, 100% of torque is sent to the front wheels, with 10% bled off to the rear under cornering to reduce the load on the front tires and balance the chassis. In slippery conditions, this changes dynamically, with up to 45% of torque output (50% with AWD Lock engaged, but only up to a maximum of 25 mph) sent to the rear as needed. The system’s greatest effect has been on the EPA highway and combined fuel economy ratings, which increase two mpg.
If that’s not enough, buyers can order a Highlander Hybrid. A mechanical carry over, the big change for 2014 is the elimination of the base model. It has been replaced by the Hybrid Limited. This places the Hybrid model on an equal footing with the range-topping gas-powered Limited, and reduces seating capacity to seven through a switch to standard Captain’s chairs in the second row.
The biggest technology news, however, is the addition of Driver Easy Speak. This is not some natural language voice activation system to control infotainment and other functions. Rather, it uses the microphone located in the overhead console to amplify the driver’s voice and broadcast it through the rear speakers at a volume level the driver chooses. Call it the “Voice of God” option for XLE and above buyers. It’s enough to make you think that, in spite of what Goto and crew might have learned in testing the prototypes on North American highways and the mountains of China and Russia, he learned the most important lessons while on vacation in that Sienna minivan all those years ago.
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By James Gaffney, Product Engineer, Precision Grinding and Patrick D. Redington, Manager, Precision Grinding Business Unit, Norton Company (Worcester, MA)