The 4.7-liter V8 delivers world-class smoothness and quietness. At highway cruising speeds, the V8 is barely audible. It delivers good power with strong torque for towing, 270 horsepower and 330 pound-feet of torque. As heavy as it is, the GX 470 is no slouch in the performance department, capable of full-throttle sprints from 0 to 60 mph in about 8.1 seconds, with a nice V8 intake roar to go with it. If you're towing anything up to its limit of 5000 pounds, this truck will handle it with ease. The bad news is that, even if you try hard, you'll probably never achieve 20 miles per gallon. The V8 is shared with the Lexus LX 470 and is optional with the Toyota 4Runner. For 2005, the V8 gets the company's VVT-i (variable-valve timing with intelligence) for improved efficiency and response at all engine speeds. VVT-i also helps the GX 470 run cleaner, earning the government's more stringent ULEV-II (Ultra Low Emissions Vehicle) rating for 2005. The GX 470 requires 91 octane (or higher) gasoline and rates an EPA-estimated City/Highway 15/19 mpg.

Lexus fits the GX with its newly developed five-speed automatic transmission, which offers quicker response and better gearing than a traditional four-speed automatic. Like the engine, the transmission is very smooth.

The GX 470 handles impressively well for a body-on-frame truck with a live rear axle. Like most SUVs, it feels heavy and ponderous with its big tires. The power steering system features different-ratio gears on the outer ends of the steering rack than in the middle, making steering quick and light in parking situations, but smoother and heavier on the highway, so the truck never feels over-assisted and never feels darty. As a result, the GX 470 feels very solid at high speeds.

Its adaptive variable suspension, which comes standard, continuously changes the shock absorber damping at each wheel individually in response to road surface conditions, speed, and 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, then switch to a firm setting for driving down a winding rural road. The system automatically increases shock absorber stiffness in transitional maneuvers. It also reduces dive under hard braking and squat under hard acceleration. The rear air suspension can raise rear ride height in rugged terrain or lower the rear end when loading cargo. Overall, the ride is 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 that's more comfortable, but not a magic carpet ride; 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 it's more responsive when cornering.

The optional Kinetic Dynamic Suspension System provides more sway stiffness when needed for crisp handling response, more comfort over bumpy roads. The system even disengages the stabilizer bars for some off-highway driving conditions, allowing more suspension travel and articulation to help handle obstacles. Lexus claims the system has been proven in World Rally Championship competition, which is another way of saying it's not a fragile gimmick.

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 control of the steering in a panic stop. Electronic Brake force Distribution (EBD) distributes the proper brake force between front and rear wheels to achieve shorter stopping distances. Brake Assist can help the driver use the full potential of the brakes in panic stops. Off road, there's enough brake pedal travel to allow precise modulation, crucial when negotiating obstacles at low speeds.

Drive the GX 470 too fast into a slippery corner or make an emergency lane-change maneuver to avoid a wreck and technology 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 spin or reduce the chance of sliding off the road.

For off-road travel there's a full-time four-wheel-drive system with locking Torsen differential that continuously apportions torque between the front and rear axles. It automatically directs power according to the traction available at each of the four corners. In normal highway conditions, power is split 40/60 percent front/rear. If the rear wheels spin, the differential can change the front/rear ratio to 53/47 percent to control the slippage. In steering maneuvers, the system sends more power to the rear wheels (29/71 front/rear) to improve tracking around curves.

Downhill Assist Control makes it easier to control the GX down steep, slippery slopes: Once activiated, take your feet off the pedals and GX slowly walks down the incline using the anti-lock brake system and electronic traction control to help stay pointed in the intended direction. Touch the brake or the gas to slow down or speed up, then take your feet off the pedals and the system resumes control to help maintain a slow, controlled speed. Downhill Assist Control even works in Reverse, in case you have to back down a hill and try again. It is a great feature that anyone can use after one lesson. Meanwhile, Hill-Start Assist Control helps keep the GX 470 stationary while starting on a steep incline.