The Lexus GX 470 is a smooth, comfortable SUV for everyday driving, and it offers some of the best off-road capability in the luxury class. Its array of onboard electronics is top-drawer, and all systems work in concert to increase the GX 470's capability and the driver's confidence.

The 4.7-liter V8 delivers world-class smoothness and quiet. At highway cruising speeds it's barely audible. The GX 470 is no slouch in the performance department, in spite of its 4,871-pound curb weight. It's capable of full-throttle sprints from 0 to 60 mph in about 8.1 seconds, with a nice V8 intake roar to go with the rush. Toyota's sophisticated electronic VVT-i (for Variable Valve Timing with intelligence) improves efficiency and response at all engine speeds. VVT-i also helps the GX 470 run cleaner, earning the government's stringent ULEV-II (Ultra Low Emissions Vehicle) rating. Peak horsepower is 263 at 5400 rpm; torque tops out at 3400 rpm and 323 pound-feet.

That's strong torque for towing. If you're pulling anything up to its limit of 6,500 pounds, this truck will handle it with ease.

Fuel economy is impacted by all this capability. EPA estimates are 15/19 mpg City/Highway. And while the GX 470 will run on unleaded regular, Lexus recommends 91 octane (or higher) premium fuel for optimum performance.

The five-speed automatic transmission offers quicker response and better gearing than a traditional four-speed automatic. Like the engine, the transmission is very smooth.

The GX 470 handles well for a body-on-frame truck with a live rear axle. Like many truck-based SUVs, it feels heavy and ponderous, but it's never a chore to drive in the daily grind. Variable-ratio rack-and-pinion steering makes the steering quick and light in parking situations, but smoother and heavier on the highway, so it never feels over-assisted or darty. As a result, the GX 470 feels solid and well-planted at highway speeds.

The adaptive suspension, which comes standard, continuously changes the shock absorber damping at each wheel individually in response to road surface conditions and speed as well as steering and braking inputs from the driver. Four driver-selectable settings are available to tailor the system to driver preferences or situations. You might want to use the softest setting for a bumpy boulevard, for example, then switch to a firm setting for driving down a winding rural road. We did this and it works well. The system automatically increases shock absorber stiffness in transitional maneuvers. It also reduces dive under hard braking and squat under hard acceleration. Air springs in the rear can raise rear ride height in rugged terrain or lower the rear end when loading cargo.

Ride quality is also remarkably refined for a truck with a live rear axle. Road vibration and pavement undulations get through, but they are damped. We found the Comfort setting produced a cushy feel, though it's no magic carpet ride as you can still feel the suspension reacting to bumps. Switching all the way to the Sport setting makes the bumps feel more pronounced, making for a less comfortable ride, but more responsive cornering.

The optional Kinetic Dynamic Suspension System provides more roll stiffness when needed for crisp handling response, without an increase in spring rate over bumpy roads. In other words, you get better handling without sacrificing ride quality. The system disengages the stabilizer bars for rugged, off-highway conditions, allowing more suspension travel and articulation to help the GX 470 step over obstacles. Lexus claims the system has been proven in World Rally Championship competition, which is another way of saying it's the real deal, not a fragile gadget.

The brakes are superb. They have a nice feel and are easy to modulate for smooth stops in everyday driving. The brake rotors are large, and all four discs are ventilated for long life and fade-free performance. (Most trucks use ventilated discs only on the front wheels.) Anti-lock brakes (ABS) help the driver maintain steering control in a panic stop. Electronic Brake-force Distribution (EBD) distributes the optimum brake force between front and rear wheels to achieve shorter stopping distances and more stable braking. Brake Assist can help the driver use the full potential of the brakes in panic stops by maintaining pressure on the brake discs even if the driver makes the mistake of relaxing pressure on the brake pedal. Off road, there's enough brake pedal travel to allow precise modulation, crucial when negotiating obstacles at low speeds.

Drive too fast into a slippery corner or make an emergency lane-change maneuver and the technology on the Lexus GX can help you out. Vehicle Stability Control helps improve control and lateral traction while cornering on dry or slippery road surfaces. The system helps the driver keep the GX on the intended path by reducing power or applying the brakes to individual wheels. This system can help prevent a skid or reduce the chance of sliding off the road.

Full-time four-wheel drive is standard. The heart of the system is a locking Torsen (torque-sensing) center differential and electronic Active Traction Control (A-TRAC) that continuously apportions torque between the front and rear axles, automatically directing power to the wheels that can best use it. In normal highway conditions, power is split 40/60 percent front/rear, meaning the front wheels are providing 40 percent of the driving force. If the rear wheels spin, the differential can change the ratio to 53/47, sending more power to the front wheels. When cornering, the system sends more power to the rear wheels (29/71 percent) to improve tracking around curves. It's a great system. The bottom line is secure traction and balanced handling in all types of conditions and situations.

Downhill Assist Control (DAC) makes it easier to negotiate steep, slippery slopes: Once activated, take your feet off the pedals and the GX slowly walks down the incline using the ABS and active traction control to keep the vehicle pointed in the intended direction. Touch the brake or the gas to slow down or speed up, then take your feet off the pedals again and the system resumes control to help maintain a slow, steady descent. It's a great feature that anyone can use after one lesson. It even works in Reverse, in case you have to back down a hill and try again. Meanwhile, Hill-Start Assist Control helps keep the GX 470 from rolling back while starting on a steep incline.

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