The GX 460 shares the same basic platform as the Toyota 4Runner, and like the 4Runner, is built to be strong enough to hold up to regular use on unpaved roadways.The 2010 Lexus GX comes standard with a new 4.6-liter V8, six-speed automatic transmission, seven-passenger seating, plus a host of luxury features the 4Runner does not offer.

The GX comes loaded with wood and leather interior trim, heated/ventilated seating, rain-sensing windshield wipers, a power moonroof, multimedia entertainment and other amenities.Like other luxury SUVs, there is a carefully crafted interior lighting scheme, programmable preferences for a variety of features, and the use of powered equipment that goes well beyond windows, seats and mirrors.

With body-on-frame construction and low range gearing, the GX 460 is far more rugged and powerful than the Lexus RX crossover.Unlike the RX, the GX offers excellent off-road capability.Recreational capabilities are quite good.The new GX can tow up to 6500 pounds with optional hitch, and it is equipped with specialized enhancements to make off-road driving safe and easy.

The GX comes standard with a full-time four-wheel-drive system with locking center differential and low-range gearing.It's a system that requires little or no input from the driver; ideal for secure travel during heavy rains and on icy roads, or on dirt/gravel surfaces.

The GX 460 competes with the Land Rover LR4, BMW X5, Mercedes-Benz GL 450, and Audi Q7.Like the European offerings, the GX requires 91-octane Premium unleaded fuel. In the end, the GX 460 is a heavily built, V8-powered, luxury SUV with many features once reserved for the top-of-the-line Lexus SUV, the LX 570.Buyers who don't need the off-road capability or seven-passenger seating might be happier with the RX350, with its better ride and easier handling.And those who really want the most from a rugged, trail-oriented mid-size SUV should shop the V6-powered Toyota 4Runner, especially if towing heavier loads is not a requirement.That said, the GX has a distinctly Lexus flavor, combining the very latest luxury features with remarkable quality and capabilities.

The GX 460's front is dominated by a four-slot grill and compound headlamps that use separate projector lenses for low beam and Halogen lighting for the high beams, with LED turn signals in the side-view mirrors.Fog lamps are mounted separately in the lower front bumper area.

At the rear, a new side-opening rear door has been designed, and the rear door window can be opened separately, allowing two ways to access the luggage compartment.The rear door, no longer a hatch, swings outward when released by pressing a hidden door handle located to the left of the license plate.The taillights use a cluster of LED elements to generate their glow.The rear wiper is mounted under the rear spoiler, leaving the back window free of obstruction.

Exterior trim differs very slightly between Base and Premium grades, with Premium GX 460s getting telltale chrome trim around the back edge of the window glass and along the bottom of the doors.

The front row is spacious, with storage bins and pockets located overhead, in the center console, and side door pockets.The front seats are eight-way power adjustable, both heated and cooled.The four-spoke steering wheel tilts and telescopes, and automatically tilts away when the Power button is pushed to shut the GX off.Between the two front seats are adjustable armrests.

The standard center stack is designed around a 4.2-inch pushbutton display that shows trip and environment data, such as temperature, cruise range, fuel consumption, climate control settings, and so on.With the Navigation system, an eight-inch touchscreen display is used, allowing for control of the Nav functions, audio, climate and phone.

Controls are nicely designed and integrated, with conspicuously high-quality wood and leather materials used throughout.Redundant switches for cruise control, audio and navigation are mounted in the steering wheel.

With the wide-view monitor, the safety backup camera becomes a camera system.The driver can check for obstructions using three different views around the GX, generated by two separate wide-angle cameras.

Second-row seating is reasonably roomy and versatile, allowing for either three passengers or two passengers with a center armrest/cupholder and overhead reading lamps.The second-row bench is split 40/20/40.The outside seats are full-size seats with available heat/cool capability.The center seat is somewhat less accommodating.

Access to the rear third-row seats is from the passenger side, where the second-row seat moves forward to allow walk-in access to the third row.We found the process a bit tricky, and the rearmost seats are not long on legroom, but for smaller passengers or short trips, the rear seats will be adequate.

The rear seats can be commanded to fold flat at the push of a button, converting the GX to a five-passenger SUV with enlarged storage.Most of the time, the third-row seats will be empty, so the power fold-flat feature on the GX is likely to be highly useful, freeing the driver from the hassle of reconfiguring the seating to accommodate changing loads.

A nine-speaker sound system that includes six-disc CD changer with MP3 capability, integrated XM radio and streaming audio via Bluetooth is standard.The optional Mark Levinson audio system is for audiophiles who demand very high performance.The system uses 17 speakers, powered by 330 watts with less than 0.1 percent total distortion, and can play DVDs or CDs in addition to files from outside sources.A rear-seat entertainment system, with remote control, is bundled with the Mark Levinson audio system as an option.

On the highway the GX cruises quietly and efficiently, turning just 1500 rpm at 60 mph.At 2000 rpm, the speedometer was showing 79 mph, and the GX is still unstressed, riding along smoothly and quietly.The six-speed transmission has a taller overdrive gear than the previous five-speed automatic, and better gear selection throughout, so it plays a big part in the GX's ease of motion.

The new 4.6-liter V8 allows for taller, more efficient gearing.The new V8 delivers more power and a 13 percent improvement in mileage.With the narrower ratios of a six-speed automatic and the added power of the new V8, the GX 460 has a more responsive character when it comes to high-speed passing and full-power, on-ramp blasts.Lexus advises that the GX 460 has been reliably clocked at 7.8 seconds, 0-60 and will do a quarter-mile in 16.6 seconds.We did not take the GX out to the track, but based on our driving, we would have no reason to quibble with those numbers.

While its highway ride is long-legged and effortless, in traffic the GX feels more like the truck-based SUV that it is.Small roadway repairs and heavily textured surfaces create a light jiggle that can be detected at around-town speeds.This we attribute to relatively low-profile 60-series tires on 18-inch wheels, and rather thick anti-swaybars used to control the GX in corners.However, bigger impacts like potholes and speed bumps are readily swallowed up by the GX suspension, which is capable of absorbing the larger irregularities of unimproved roadways.Our route took us across a series of speed bumps, where we quickly noticed the faster we hit them, the better it felt.

The four-wheel disc brake system responds well to light pressure at the top of the pedal, which is how this family wagon would normally be driven.All-out stopping power is consistent with a vehicle designed tow up to 6500 pounds, when truly powerful brakes are a requirement.While there is some front-end dive upon very hard braking, more than the average sedan, given the nature of the vehicle, we'd consider front-to-rear suspension compression well controlled.

Cornering is actually quite good for a vehicle of this size, height and weight.Body roll is well controlled by the same stout swaybars, allowing the GX to track through corners predictably without need for correction, and the stiffer wheel and tire combination works to enhance stability.Lexus has gone to electric steering, which has had a reputation for relatively numb feedback characteristics, but this is not a sports car, and the packaging advantages include significant mileage gains.This newest version of electric steering seems more thoughtfully tuned, with a better range of power assist, leading to a nice turn-in feel and stable tracking through sweepers.The GX is not the kind of vehicle we'd be inspired to toss into corners, but the suspension travel is not so long as to create wobbles.We wouldn't call it nimble, but in ordinary use the GX is easy to drive and quite painless to operate.

The GX is always in four-wheel drive, a mode that was completely transparent to us as we drove.There is no sense of torque steer, and no scuffing or binding up during full-lock, low-speed maneuvering that might occur with part-time 4x4 systems.The use of a torque-sensing center differential allows the GX to continuously adjust power distribution from wheel to wheel as traction permits.Traction is further enhanced with the electronic traction system Lexus calls A-TRAC, so wheel slip is quickly controlled on surfaces like wet grass or slippery pavement.There was nothing extremely challenging about the weather or the dirt roads we addressed during our off-road driving, but the hills and service roads of the Vessels Ranch were enough to get the GX thoroughly dusty.

Finding a level spot, we actuated low range using a small lever just below the shifter, and saw that it nicked in and out of 4-Lo immediately.It's necessary to enter Neutral to access low range, but short of that, 2.56:1 gearing is available practically on-the-fly.Because of the gearing, and the adoption of KDSS, the Lexus GX 460 is one of the very few mid-size SUVs with genuine off-road capability.

KDSS (Kinetic Dynamic Suspension System) is a remarkable electronically controlled system that unhinges one end of the anti-sway bars that would normally limit wheel travel.Limiting wheel travel is a good thing on pavement, but off-road, the opposite is desirable.KDSS offers a way to have the best of both worlds.It works automatically, without driver intervention, any time a wheel is lifted off the terrain while the vehicle is in low range.We've tested the system in the past on the Toyota Land Cruiser, and found it dramatically improves a vehicle's ability to avoid getting stuck while crossing highly irregular terrain.

Lexus Enform is the latest in Lexus telematic systems, and it comes standard on the GX.Enform is a subscription-based live-operator assist system that enables real-time assistance without having to fuss with navigation programming.To test it, we pushed the button, an operator picked up and downloaded directions to our lunch destination.We felt guilty asking a live operator to direct us to a burger joint, but it is nice to know that someone is standing by 24/7.Enform is optional, bundled with Navigation.Another system, Safety Connect, is standard on the GX and provides automatic collision notification, stolen vehicle location, emergency assistance and enhanced roadside assistance.

As the miles rolled on in the quiet cabin, it was easy to speak at it using a low tone of voice, and the sound system provided clean, accurate sound reproduction.This is not surprising: the Mark Levinson system has 17 speakers and enough clean power to allow for listening at very high volumes with practically no distortion.We didn't have a back seat passenger during our drive, but we did listen from the back seat later on, and sure enough, the sound is just as good in the back seat as the front.It's an option that, while on the pricy side, will truly be appreciated by those who love their music.

John Stewart filed this NewCarTestDrive.com report after his test drive of the Lexus GX near Del Mar, California.

The GX 460 Premium model ($56,765) upgrades with tri-zone air conditioning, automatic HID projector-beam headlights, auto-tone control audio, cargo tonneau, Adaptive Front Lighting System, auto tilt-down mirrors, heated steering wheel, heated second-row seats, and the Adaptive Variable Suspension.

Options include the Navigation System ($1,990) or the Mark Levinson Navigation audio package ($3,930).The Wide View Monitor system ($3,170) includes the pre-collision system, Driver Attention Monitor, Lane Departure Alert, Intelligent High-Beam Headlamps, Dynamic Radar Cruise Control and crawl control; parts of the package can be purchased separately.

Safety features that come standard on all models include advanced frontal airbags, side curtain airbags, three-point seatbelts in all positions, anti-lock brakes (ABS), electronic brake-force distribution (EBD), Brake Assist, Traction Control, Vehicle Stability Control, tire pressure monitor system.