2008 Lexus LS600h Road Tests

The LS 600h comes with the latest full-hybrid powertrain and all-wheel drive.

Swift and stable on the road, the LS 600h L blends luxury, performance and ecologically efficient innovations to make a unique luxury car. The full-hybrid drive system delivers performance on a par with a 6-liter V12 engine, yet with mileage comparable to a V6 powered sedan. According to Lexus engineers, the LS 600h L produces exhaust emissions nearly 70 percent cleaner than the cleanest competitors.

The LS 600h will be offered strictly as a long-wheelbase model, hence the L in the model nomenclature. The additional length this stretched version offers translates into just a little less than five inches of additional rear leg room. Nine colors are available, in a palate of pearlescent and metallic paints.

The interior is crafted in subdued, tasteful colors. Wood and leather materials are used to accent touch points such as the steering wheel, assist handles, instrument panel, and shift knob. In keeping with Lexus design philosophy, every effort has been made to cleanly integrate controls and features without adding clutter. Interior details stand up to close inspection, even down to the stitching in the seats and uniform action of panel covers. The effect is that nothing stands out, because the interior details have been executed at a uniformly high level.

Ride comfort is equivalent to what luxury car buyers should expect. Road vibration is minimal and there is little harsh impact or uncontrolled rebounds, even at high speeds. More impressive is the balance of ride quality, low noise and predictable, sure handling. This effect comes from a new, multi-link air-spring suspension, and an optional active power stabilizer package.

Because of a relatively short turning radius and electronic power steering, the LS 600h is surprisingly easy to maneuver and park. For those who are less than perfect at parallel parking, the Lexus Park Assist feature can be used to allow the car to park itself. Electronic steering also enables the LS 600h to optimize steering control according to vehicle speed, so drivers get both easy maneuvering at low speeds and firm control at high speeds.

The LS 600h has been designed with a full suite of advanced safety features. Many of these are enhancements to the brake and steering systems. As a group, they function to detect possible problems, enhance brake control, enable the car to avoid obstacles, and minimize severity of unavoidable collisions.

The LS 600h is a roomy, distinctive, limited-edition sedan with world-class safety and performance.

Upgrades are based upon a choice of three rear seat configurations, which include an executive Class Seating package that converts the interior into a four-seat configuration and includes a 45-degree reclining right rear seat with massage feature, infrared body-temperature sensors and 18-inch wheels.

An Active Power Stabilizer package enhances handling and includes 19-inch wheels.

A unique Launch Edition LS 600h were sold through the summer issue of the Neiman Marcus InCircle catalog. About 100 units came with a three-piece set of leather luggage custom-designed to fit into the trunk by an Italian leathersmith. The Launch Edition models include exclusive exterior paint, detailed interior seat trim in white leather, 19-inch wheels and distinctive badging.

Safety features include the latest integrated safety system from Lexus, called Vehicle Dynamics Integrated Management. However, the Advanced Pre-Collision System is optional.

Use of LED lamps, which require only 58 watts of voltage, works to create a complex, technical headlamp area. The headlamps are computer controlled. They re-aim themselves to the left or right as the vehicle is steered to better illuminate corners on dark roads.

Wheels are sized according to the options package: 18-inch for better ride, 19-inch for better handling. The wheels receive extensive buffing and their shape was analyzed to create a form with shade depths that shift when the vehicle is in motion.

The effect is to create a sense of speed and stability, strength and dignity, and above all, quality.

If you've never driven a hybrid, the first thing you'll notice is the Power button. With your foot on the brake, touch the Power button and the car boots up. The indicator needles illuminate, the speedometer and tachometer rings fade in, followed by the shift range indicator. Finally, the engine starts.

You'll notice that the LS 600h cabin is understated and relaxed, yet meticulously executed in very high quality materials. Use of fine-grain leather extends onto the instrument panel, upper front doors and armrests. Electro-luminescent Optitron gauges are standard. The center console is positioned at the same height as the door armrests. Seats are 12-way power except for the driver's seat, which is 16-way and has three-position memory.

The shifter is trimmed with wood and chrome, and it actuates a continuously variable transmission, or CVT, that has an eight-speed sequential sport-shift mode.

The navigation system has a 30 GB hard drive. While it is probably not the easiest navigation system to learn to use (there is a large separate manual), the screen is bright and the buttons easy to reach.

In the back seats, the LS 600h has almost five inches more legroom than the standard LS. This permits especially generous passenger seating options. In many ways, the rear compartment is designed to be the most comfortable section of the car.

Three different rear seating packages are available, each with varying degrees of comfort, which allow buyers to build out the available rear space to whatever degree they wish. The rear climate control system is engineered into the car, using infrared radar to scan rear seat passengers for body temperature. There are dual-zone controls for rear seat passengers, directing air through additional rear air ducts in the B-pillars, above the doors and above the rear passenger head area. The air conditioning unit also provides cooling for the hybrid battery, located under the rear seat.

We felt compelled to try the ultimate rear seat package, called Executive Class Seating. This makes for a back seat very similar in size to a business-class row in a jumbo jet, with two side-by-side seats that recline deeply, with a fixed console between the two and a fold-out table. One of the two seats has an ottoman leg rest. It reclines up to 45 degrees and tilts 17 degrees. There is a massage feature, seat heater and cooler, rear cool box, and a rear entertainment system with a power ceiling mounted 9-inch screen for DVD viewing.

The Mark Levinson surround sound audio system uses 14 speakers and a 450-watt amplifier to generate the perception of sound throughout the cabin. We listened to the system from the rear seat. The experience is like sitting in a recording studio. You can hear each musician playing, separately and together, as if they are sitting on different parts of the stage, with a singer at the center, bass at the left and backup vocals on the right. Percussion is particularly flavorful. You can hear the sound of a brush on a snare, or the clap of a drumstick on the side of the can. Once the Levinson electronics have divided the sound into numerous channels, it becomes possible to hear the texture of each sound. In a car this quiet, sound quality remains intact while the car is running, with the A/C on. You could play your favorite CD and hear sounds you never heard before. The downside is, once you become used to an audio system this clean and accurate, nothing else is going to sound right.

Lexus designed the LS 600h to provide performance equivalent to V10 and V12 engines. Powered by the combination of a new 5.0-liter V8 and two new-generation electric motor/generators, the LS 600h readily attains a top speed of 135 mph, at which point an electronic limiter gently intervenes and slowly backs the car down to 130 mph.

At 120 mph, the tach reads just 3000 rpm, 1000 rpm below its torque peak, with the red line set at 6500. Because of the torque of the electric motor, 0 to 60 can be attained in 5.5 seconds, even in a car that weighs 5049 pounds. That's pretty quick.

The engineers at Toyota/Lexus can configure their Hybrid Synergy Drive for high mileage, high performance, or any combination of the two. In the LS 600h L, the system is biased toward performance. Midrange acceleration, in particular, is enhanced. The LS 600h L accelerates from 50 to 70 mph in 3.5 seconds.

Unlike a V10 or V12-powered luxury car, the LS 600h is EPA-rated to deliver 21 combined mpg, something more akin to a V6 powered mid-size sedan.

The hybrid drive system uses two powerful electric motors and a newly developed battery pack that is lighter and stores more electricity than previous systems. The system is capable of driving the car in electric only mode, or with a combination of gas engine and electric motor. The battery system consists of 288-volt DC Nickel Metal Hydride pack located behind the rear seat. In the trunk is a 12-volt auxiliary battery to power the audio system, navigation and lighting. The electric motors, MG1 and MG2, perform specific functions. Each can operate as both a motor and generator, although MG1 is used as a starter motor and provides no drive force. The engine-driven generator, MG1, can charge the battery pack or provide additional power to the drive motor, MG2, as needed.

Even though the hybrid is equipped with regenerative brakes, which recharge the battery as the brakes are applied, brake feel is typical of a standard car equipped with strong disc brakes, an impressive engineering achievement.

The LS 600h is the first North American hybrid that can operate in EV Mode, in which the vehicle will stay in electric-only mode at speeds below 25 mph for about a half mile. This feature might be useful to glide into the garage silently if you get home late, or get to a gas station if you ran out of fuel or maybe for use in stop-and-go commuter traffic.

On the road, the LS 600h feels like a rear-wheel-drive car, but is actually all-wheel drive. A computer mixes torque from the V8 and electric power source, feeding through a continuously variable transmission to achieve a balance between front and rear wheels. We noticed no hunting between front and rear, no sense of sorting from wheel-to-wheel as the car passes over different surfaces. There is none of the torque steer that accompanies high-horsepower front-wheel-drive cars, which can be detected in the front-wheel-drive Lexus RX 400h SUV. With the LS 600h L, peg the throttle and acceleration is smooth and linear, with an uncanny absence of drama. Using the tachometer, we were able to discern the moment when the electric motor assist kicked in, but only under full throttle. To the average driver, the hybrid system would be largely unnoticed.

The reduction in noise and vibration is a benefit from the air springs, which can be computer controlled for ride height, and have no metal parts to transmit noise.

As we drove at high speeds on Toyota's 10-mile oval test track, we had to remind ourselves that this is a SULEV, a Super Ultra Low Emissions Vehicle, with substantially cleaner emissions than vehicles with a conventional engine, and exhaust cleaner than the ambient air in some major cities.

The interior may be roomy, but from behind the wheel, the LS 600h feels like a smaller car. Especially at low speeds, steering is light and responsive, and the turning radius is surprisingly short for a car in this class. So much so, in fact, that the car lends itself to spirited driving on winding roads. Pavement dips, cracks and surface variations can be heard, but generally not felt, during cornering exercises. Especially with the optional active stabilizer, the air suspension offers the predictable handling of a rear-wheel drive car, maintaining a stable posture with minimum pitch or roll.

A BMW 7 Series sedan offers sharper handling, but its larger wheels and lower-profile tires let more road noise through to the cabin and more vibration to the wheel. With the optional active stabilizer package, the LS 600h L seems to deliver BMW-like control and handling, with less noise or vibration.

Active safety is enhanced by advanced electronics: Steering is electronically controlled, so it can offer a wide variation of ratios depending on speed and throttle conditions. The electronic power steering system partners with the vehicle dynamics integrated management system (VDIM), making minor adjustments to the front wheel angle for improved stability when roads become challenging. So in many ways, VDIM is a performance-enhancing system.

VDIM is also a safety system, monitoring input from the brakes, stability control sensors, steering wheel, throttle and engine torque. The system can actually anticipate the onset of a skid or slide. Using a combination of selective braking, throttle and steering control, the system can correct driver misjudgments in a manner essentially transparent to the operator. We tested VDIM extensively at the Toyota Proving Grounds by intentionally overdriving into corners, entering slaloms at impossible speeds, and speeding toward obstacles until they became unavoidable. We found that the degree to which VDIM can correct gross operator error is uncanny. It's a system we wish could be on every car.

On the LS 600h L there are other innovative safety systems that could be life-saving. One is the Advanced Pre-Collision System (APCS). It can detect pedestrians in the vehicle's path using two small cameras and millimeter-wave radar. A driver monitor system, mounted inside on the steering column, actually checks the driver's face. If the camera sees that the driver is not looking directly ahead for a few seconds or more, and if an obstacle is detected ahead

We reluctantly tested the Intuitive Park Assist system, thinking anyone who knows how to parallel park will consider this an unnecessary, slightly insulting adornment. However, it really works. Actually, it works great. We found ourselves using it over and over. The trick is to scan in the exact size of the parking space, then keep a foot on the brake while the car automatically maneuvers itself into the spot. It takes about 10 seconds.