Interactive hybrid cars resource
GreenHybrid Home - Hybrid Cars
Hybrid Cars Discussion Forums
Hybrid Articles
Hybrid Mileage Database & Car Specs
Hybrid Car Photo Gallery
Shopping Guide for Hybrid Cars

From GreenHybrid

Jump to: navigation, search

Driven: 2006 Toyota Highlander Hybrid
Contributed by: Jeff_Y
Posted by: Jason
Published on: 01-01-2004  

Article Content

Up for a 29 mpg, 7-passenger SUV (for $33K)?

by Jeff Yip

Copyright © 2005

PHOENIX – OK, after an afternoon driving the hybridized Highlander in urban sprawl and in the mountains, we can vouch for the power part of this equation. Now let’s pray that the EPA numbers scored by this next wave of Toyota hybrids aren’t just vapor. The public get a chance to find out in early June when this bad boy hits showrooms.

A well-executed one-two punch is not just devastatingly effective; it’s a pugilistic work of art. If the Prius I and II were feints and probes, the gasoline-electric Lexus RX 400h and Highlander Hybrid constitute a double-tap against Toyota’s opponents.

Will consumers who want to save at the pumps, but need more than a compact SUV, finally have their cake and eat it too? It might be time to break out the dessert forks.

Toyota reports that the EPA city/highway economy numbers for the 4x2 hybrid Highlander are 33/28, for a combined 30 mpg. Meanwhile, the 4WD-i versions get fuel efficiency ratings of 31/27, or 29 overall. (The benefits of the hybrid’s electric propulsion are greatest in stop-and-go use.)

Unless you’ve had to fill up an SUV tank recently, you may not fully appreciate those EPA estimates. The one rub here is the credibility gap between the EPA ratings for hybrids and real-world fuel consumption. We’ll need to live with a production model to determine whether the numbers are in the bull’s-eye -- or just bull.

What’s real, though, is the “warp drive” factor Synergy hybrid system adds. The big bonus (and grin) will be on freeways when the right foot is firmly applied. Thanks to its continuously variable transmission and power-melding firmware, the traditional press-your-back-into-the-seat drama is replaced by a delightful linear rush. One more thing: while this Highlander may be fast, thankfully it’s not furious. The extra oomph for what would be a typical vanilla Toyota V6 doesn’t come via noisy low-restriction mufflers.

As one door closes, another opens

General Motors’ all-electric Saturn EV1 had earned itself a cadre of fans, including Hollywood luminaries like Woody Harrelson and “Baywatch” babe Alexandra Paul. EV1ers have passionately protested being forced to part with their leased two-seaters. Who could blame them when gasoline was running $2.50 a gallon or more? You don’t have to be a Big Name or a registered member of the Greens to mourn the loss of a vehicle that will run around town all day, romp along at up to 80 mph and never brake for a gas station. When the lease was up, the jig was up and the General came calling. GM’s small band of early-adopter evangelists became antagonists in a public relations dust-up. GM would have no EV2 to show as return on investment and the EV1’s final environmental mission was to sacrifice itself to recycling.

Fast-forward to 2005. Toyota wears the leadership mantle in delivering vehicles that help address the global energy crisis. This year alone, it expects to sell 100,000 Priuses.

Toyota’s hybrid die was cast in the mid-1990s. “It was decided that nearly every phase of our hybrid development program would be done in-house. No partnerships, no contractors, no suppliers of major components and systems,” said Ernest Bastien, vice president of Toyota’s vehicle operations group.

Toyota developed the 2006 Highlander and the Lexus 400h hybrids in tandem, and their drivetrains are identical. The gasoline powerplant remains a 3.3L V6; the 3MZ-FE is rated at 230 horsepower. The Hybrid offers up to 268 peak combined horses, thanks to its fourth-generation Synergy system. On 2WD (or FWD) the Synergy Drive uses two motor generators that serve dual duty, as their names suggest.

Four-wheel-drive Highlanders get a third motor generator for the rear transaxle. This MGR, as Toyota dubs it, is a bundle of gee-whiz tech having no planetary gears, bands, clutches, hydraulics or drive chain. But when conditions warrant, the 90-pound wonder sends power to the Highlander’s rear axles.

This on-demand electronic “4WD-i” scheme allows four-wheel launch torque and 0-60 mph sprints around 7.3 seconds, which we confirmed with a stopwatch. A CVT replaces the five-speed automatic used in conventional Highlanders.

If your recreational style leans toward boating or motorcycling, note that the Highlander Hybrid is rated to tow up to 3,500 pounds. (That’s the same weight for conventional 4x4 Highlanders and 500 lbs. more than gas 4x2s.)

Toyota takes pains to point out that the 4WD-i Highlander is not meant for full-time four-wheelin’, so if you had dreams of going rock climbing in your Highlander Hybrid we have one word, wise guy: fuhgetaboutit. Just sit back and enjoy the extra traction in rain and snow (and the extra shots of juice those back wheels will produce when they’re in regenerative mode).

The flow of power

In a nutshell, here’s how the Synergy System works.

Under the second-row seat is a 288-volt nickel metal hydride (Ni-MH) battery pack. That DC power is sent to a booster, which, in turn, sends 650 VDC to an inverter, which converts the juice to alternating current for the motor generators. Motor generator 1 (MG1) is used as the starter for the V6. MG2, the unit that contributes power at the wheels, is a 123 kW (165 hp @ 4,500 rpm) motor that runs up to 12,500 rpm (twice that of the Prius’). Torque is rated at 247 ft.-lb. from 0-1,500 rpm. MG1, meanwhile, controls the output speed of the transaxle through a planetary gear set. And, of course, during braking, both units generate electricity which is sent to the batteries.

In this super ultra low emissions hybrid, the control interface and vehicle characteristics are a little different. (Unless you drive a Prius.) The shift pattern for the hybrid is the familiar P, R, N, D but a “B” position follows “Drive.” The B is for engine “braking,” which helps regenerate electricity.

The instrument panel uses the attractive (and effective) “optitron” crisp illuminated white-on-black lighting pioneered years ago in the Lexus LS. But on hybrids, the tachometer normally at the far left is replaced by a power meter. The indicator gives readouts for total output (engine and motors) as well as energy recovery (200 Kw). A blue zone tells the driver when the hybrid is regenerating electricity and using engine braking power.

Meanwhile a center panel – used only on vehicles without navigation systems – indicates energy flow. Additional info includes trip meter and odometer, outside temperature, average miles per gallon and current miles per gallon.

The LCD on Highlander Limiteds with navigation is multi-tasking. An energy monitor screen mode reports energy flow from the engine, motor and battery. The consumption screen indicates current mpg, history of fuel consumption in 5-minute increments and 50 watt-hour increments of regenerated energy. And when the shifter is in neutral, the screen cautions drivers to put the shifter in P. (Shifty characters need to know the high-voltage battery pack will not charge in neutral.)

To get the most miles from a tank of gas, the Highlander hybrid uses electric power steering, air conditioning compressor and water pump. (The electric water pump is only used when the engine is off to stabilize heating; a mechanical pump circulates coolant when the gas engine is running.) The fuel tank’s walls are thicker (2.0mm vs. 0.8mm on regular Highlanders), because the tank is pressurized to about 3.5 PSI. Unfortunately, the potential cruising range of the hybrid is reduced by its 17.2-gallon tank; conventional Highlanders have a 19.1-gallon fuel tank.

The Highlander’s electric power steering assist kicks in only when the computer sensors indicate it’s needed. EPS uses no power steering fluid, so that’s one less chore when doing under-the-hood checks. But the high-tech gizmo, which Toyota says improves fuel consumption by about 1.5 percent, is bound to make steering-rack damage an even costlier proposition than usual. Just one more reason to heed Toyota’s warning and stay on paved roads. And just take Toyota’s word and kindly ignore the 28/21 degree (2WD) and 29/22 degree (4WD) approach/departure angles listed in the Highlander’s spec sheets.

The brake-by-wire system (did you expect anything less?) has been tweaked for smoother braking feel. And hybrids get beefier, ventilated rotors up front: 12.6 inches in diameter vs. the solid 11.6-inchers used in non-hybrids. Rear brakes are identical: 11.3-inch solid discs.

Safety and handling are increasingly becoming the domain of computers and sensors. (As always, technology can be overridden by human stupidity). The hybrid Highlander is loaded with tech. First, the passive measures: standard advanced airbags for driver and front passenger inflate according to collision severity. A sensor monitors the weight bracket of the front passenger to determine whether to trigger the airbag. Also standard are front-seat-mounted side airbags and first- and second-row side curtain airbags with rollover sensor.

Luddites are hereby warned to skip to the next paragraph. Proactive safety is courtesy of Toyota’s VDIM (vehicle dynamics integrated management). VDIM ties together various components to enhance safety, control and enjoyment of the Highlander’s handling. If you take a dim view of alphabet soup and jargon, grit your teeth: the systems include anti-lock brakes (ABS), brake assist (BA) and electronic brake force distribution (EBD), traction control (TRAC) and vehicle stability control (VSC).

Unlike the distinctively styled Prius, “bi Highs” (bi-powered Highlanders) are a lot tougher to spot in a mall parking lot. Besides understated “hybrid synergy drive,” badges, hybrid Highlanders have unique LED taillights, split-spoke 17x7-inch alloy wheels and 225/65R17 tires. (Conventional Highlanders have 16-inchers as standard.)

A ‘significant’ model change

Toyota has aimed the seven-passenger Highlander at consumers who wanted hybrids to evolve into a vehicle that was “roomier, more functional and more versatile,” said Bastien. “It’s not just about being green, or more fuel efficient, or even the higher level of performance. Rather, it is all about delivering a better total package.”

All Highlander Hybrids will be three-row, seven-passenger models. The list of standard features – including roof rack, power driver’s seat, tilt steering wheel and privacy glass in the rear -- is extensive and about what you’d expect from Toyota. The Limited trim package coddles buyers with in-dash six-CD changer with audio controls on steering wheel, anti-theft/immobilizer system, leather seating and steering wheel cover, power front passenger seat, moonroof, fog lamps, auto-off headlights and automatic air conditioning with humidity sensor.

So, you ask, what’s the tab?

The bottom line is that hybrids, like trendy seafood, will fetch whatever the market will bear.

In these United States of America, the dealership is free to set whatever price it wants. But let’s look at what Toyota – which has the power to allocate units of what is sure to be a hot-seller -- says. Its suggested retail price for a base 2WD Highlander Hybrid is $33,030. The base 4WD-i is $34,430. The top-of-the-line Limiteds, meanwhile, are $37,890 for the 2WD. The 4WD is $39,290.

Before your fingers dance across the calculator in a mad dash to figure how many months or years it would take to recoup the premium (including any added “market profit”) for a hybrid Highlander, it may be helpful to frame the issue this way:

What are the chances a performance enthusiast (or SUV owner) would shell out $5,000 – including installation and an eight-year warranty backed by a first-class manufacturer -- for a system that delivers a 16.5 percent boost in horsepower and improves mileage 38 percent?

Yeah. You got it. The typical tuner dude (or tuner diva) would be on that like white on rice. And, remember, you get 17s, third-row seat and side airbags thrown in.

Inquiring minds already envision a Sequoia (or similar titan) squeezing out 22 mpg, instead of a painful 13 or 14 around town, where most of us really drive.

Jeff Yip is a veteran reporter whose work has appeared in the Los Angeles Times and New York Times.