A Subtle Shade of Green
Page 1: Introduction
Kailua, HI -- luxury suvs have long been loathed by the environmentally conscious. All that leather and space, the big engine, the heavy weight, and abysmal fuel economy to boot.
They are considered by some to be modern day white elephants -- comfort for the sake of it, size just because you can afford it, waste because no one really cares.
That may well be changing, thanks to Lexus and the latest hybrid vehicle to be introduced in North America, the 2006 Lexus RX 400h. Now even luxury SUVs and their owners can quietly take a role in saving the planet -- without joining Green Peace or giving up any of the creature comforts or performance they’ve come to expect from the vehicle they drive. Based on the current Lexus RX 330 platform, the RX 400h hybrid combines a 3.3-liter V6 with a permanent magnet electric motor up front and an electric motor for the rear wheels to produce 268 total horsepower.
The 2006 Lexus RX 400h's front electric engine develops 247 lb.-ft of torque, while the rear motor generates 96 lb.-ft. of torque through a six-time gear reduction, boosting overall rear wheel torque to an impressive 650 lb.-ft. of yanking power. That's good enough to achieve a 3,500-lb. towing capacity. Lexus also includes a third electric motor, mounted at the bell housing, to function as a generator, engine starter, ratio controller for the continuously variable transmission (CVT), and part-time charger for the 288-volt battery pack. Taken as a whole, the system effectively produces performance similar to a V8, while sipping fuel like a compact four-cylinder sedan.The technology that drives the 2006 Lexus RX 400h, however, is not completely transparent. When you insert and twist the key in the RX 400h’s ignition, don’t be surprised when the engine doesn’t start. You'll sense that the electric air conditioning will quietly kick on, and the electric power steering will ease steering input under your fingertips. Otherwise, it’s eerily quiet inside the RX 400h. Place the CVT into gear, push down on the accelerator, and the front electric motor pulls you away without using the gasoline-fired V6, up to 42 mph, given proper conditions.
Adding additional pressure to the accelerator makes the V6 come to life, and the CVT seamlessly streams through the ratios, maximizing the powertrain’s torque curve. Mashing the throttle to the floor takes the Lexus RX 400h from mild-mannered SUV to hybrid hyper drive vehicle, as the battery packs deliver a full surge of voltage to the front and rear electric motors. Make no mistake -- under full acceleration, the Lexus RX 400h feels as though a small block V8 has been transplanted between the front shock towers, though the muted exhaust of the V6 and whine of the electric motors audibly remind you otherwise. Let off the gas and the V6 stops running while all three electric motors go into regenerative braking mode to recharge the nickel metal hydride batteries.
Page 3: Economy
Despite a powertrain that mimics a V8, the 2006 Lexus RX 400h delivers impressive fuel economy. Preliminary EPA estimates given by Lexus are 30-mpg on the highway and 26-mpg in the city –- about the same as a Toyota Matrix with all-wheel-drive and an automatic transmission. We took a pre-production Lexus RX 400h on a 412-mile loop around the Big Island of Hawai’i that included city, mountain and highway roads. Based on the RX 400h's trip computer, our light-footed jaunt through paradise averaged an optimistic 34.4 mpg.Though we tried the Lexus RX 400h on a couple of dirt roads, Lexus engineers were quick to point out that although the RX 400h is technically an all-wheel-drive vehicle, it’s not a capable off-roader. True, the mass majority that will buy this hybrid SUV won’t ever take it on anything more challenging than a graded dirt road, or on snow. However, it is important to note that sand is to be avoided. Since the rear electric motor is air-cooled, there’s a concern for excessive heat build up, which would cause the system to shut down (to protect itself), temporarily leaving the RX 400h's passengers stranded. Not good when the tide is coming in. If you want to go off road, or drive on the beach, the 2006 Lexus RX 400h is not for you.
Don't expect fellow motorists to immediately identify you as environmentally responsible if you're driving a 2006 Lexus RFX 400h. It looks like a clone of the RX 330, though Lexus sprinkled a few practical additions to the design for the purposes of differentiation, such as a new front grille, a secondary bumper grille to aid electronics cooling, round fog lamps, and rear LED tail lamps.
Page 4: Safety
Behind the wheel, the cabin has all the amenities you’d expect from a Lexus –- a buttery leather interior, plenty of soft-touch plastics, tasteful wood trim, and perfectly engineered ergonomics. Where the RX 400h differs from the RX 330 is in the replacement of the instrument binnacle’s tachometer with an energy meter displaying the amount of power generated by the hybrid powertrain. Other changes include a multi-function display, which allows the driver and passengers to monitor the gas/electric power distribution, and which contains the optional DVD-based navigation system.As with all Lexus vehicles, safety is a prime consideration, and the 2006 RX 400h comes equipped with the latest safety equipment. In addition to front, front-side and side-curtain airbags, the windshield and front-side windows feature a water-repellent coating, and there’s a rear-view camera when the RX 400h is equipped with the navigation system. One would expect rain-sensing wipers and HID headlamps (and they’re standard), but the adaptive front lighting system, which computes the RX 400h's speed and steering angle, automatically rotating the headlamps into a curve, is a wonder on dark mountain roads.
Page 5: Wrap-Up
The 2006 Lexus RX 400h is a wonder in other ways as well. Because it combines powerful technology with expected luxury amenities and subtle changes to the vehicle’s appearance, the result takes the wasteful premise of luxury SUVs and turns the RX 400h into a model for efficiency. Best of all is that Lexus has done so in a subtle way that’s sure to have RX 400h owners whispering, “Look at me. I’m green.”Pricing is still not finalized. Lexus buyers have indicated that they might pay as much as $5,000 over the current RX 330 for the hybrid RX 400h, but the RX 400h comes better equipped in standard guise, so the actual price hike is likely to land in the low $40,000 range. If spending somewhere in that neighborhood is too much of a commitment to improve gas mileage while reducing emissions, the next step down on the hybrid SUV scale is Ford’s Escape Hybrid -- at least until the 2006 Toyota Highlander Hybrid hits the market. With a mere 24,000 units destined for America’s shores this year, we suggest you get friendly with your local Lexus dealer if you’re looking to score a 2006 Lexus RX 400h. As with the Toyota Prius and Ford Escape Hybrid, demand is likely to exceed supply.
Page 6: FAQs
What kind of gas mileage can I expect from the 2006 Lexus RX 400h? During our day-long test drive, we averaged between 30 and 35 mpg. Lexus says that the RX 400h will deliver the fuel efficiency of a typical compact sedan, estimating 26 mpg in the city and 30 mpg on the highway. For comparison, the EPA says a 2005 Toyota Matrix with AWD and an automatic transmission gets 26 mpg in the city and 31 mpg on the highway.
What’s the best thing about the Lexus RX 400h? Clearly, the technology. With two electric motors and a traditional engine driving the wheels, and a third electric motor handling accessories, the Lexus RX 400h's complexity is enormous but the pay-off is significant. The 2006 Lexus RX 400h provides performance, luxury, and utility with efficiency and environmental responsibility. It could be the ultimate automobile.
What’s the worst thing about the Lexus RX 400h? Price and availability. With only 24,000 scheduled for production and thousands of pre-sold orders at the dealership, it won’t be easy to get a 2006 Lexus RX 400h. The few that haven't been snapped up are likely to sell for well over sticker price, if "market adjustments" to the stickers on other hybrid models are any indication.
Page 7: Specifications
Test Vehicle: 2006 Lexus RX 400h
Engine Size and Type: 3.3-liter V6, 123kw electric front electric motor, 50kw electric rear motor.
Engine Horsepower: 208hp, 167hp, 68hp
Engine Torque: 212 lb.-ft., 247 lb.-ft, 96 lb.-ft
EPA Fuel Economy: 26 city and 30 highway (estimated)
Max Towing Capacity: 3,500 lbs.
Max Seating Capacity: 5
Competitors: Acura MDX, Audi allroad, BMW X5, Cadillac SRX, GMC Yukon Denali, Hummer H2, Infiniti FX, Jeep Grand Cherokee, Land Rover LR3, Lexus GX 470, Lincoln Aviator, Mercedes-Benz M-Class, Porsche Cayenne, Saab 9-7X, Volkswagen Touareg, Volvo XC90