The LX moves out readily at part throttle, creating the sensation of power in reserve. The engine is an advanced 5.7-liter V8 shared with the Tundra pickup truck and Land Cruiser SUV. It's built for torque, and it produces a lot of it, 403 pound-feet, early in the rev range. More than 90 percent of the torque is available before 2200 rpm, so most of the time the engine is loafing along with very low effort, which adds to the quiet, untroubled manner the LX conveys on the move. This ability to provide power without spinning the engine faster gives the LX a different character than the Cadillac Escalade or Land Rover Range Rover, which produce their peak torque at higher rpm levels.

The new six-speed transmission has a very low first gear, complementing the engine's torque with enhanced mechanical leverage. The net effect, once again, is low effort in ordinary driving. At higher speeds, the six-speed offers a double overdrive combination, with a sixth-gear ratio of just 0.588. This very tall cruising gear allows for quiet, effortless cruising. At 2000 rpm, our test unit indicated a speed of 72 mph. At speeds over 75 mph we were able to detect some wind noise coming from the mirrors, but thanks to careful noise isolation work, the powertrain is not the source of noise or vibration until much higher speeds are demanded.

Top speed is electronically limited to 137 mph. As you might expect with a four-wheel-drive of this considerable heft, the LX remains composed and relaxed even at speeds well beyond the recommended norm on America's superhighways. In bad weather, the LX really comes into its own, with a torsen limited-slip center differential biasing torque to maximize traction.

Drawing from its Land Cruiser heritage, the LX has the guts of a true 4x4. The four-wheel-drive system has four modes, actuated by a toggle switch on the center console. It's possible to lock the center differential in high range or low range, or leave it open in either range. Normally, most people will be operating in the unlocked, high range mode, which should deliver the best mileage. When there are patches of ice or water on the road, locking the center differential helps maintain grip as individual wheels encounter slippery surfaces. When the going gets really bad, such an ice storm or if deep mud blocks the path, locking the center differential and using low range would supply maximum balance to move forward without getting stuck.

Unlike the iconic 4x4 Land Cruiser, the LX does not offer locking differentials, relying instead on electronic traction control (A-TRAC) to prevent wheelspin. Our (considerable) experience with A-TRAC is that it provides enhanced traction and off-road capability sufficient for any unplanned event, and then some. The Toyota Land Cruiser, with available electronic lockers, might be better suited for those who expect to use their SUV as a 4x4 recreation vehicle, but both vehicles have multi-terrain ABS, which works at low speeds on-road or off, and both vehicles have Crawl Control. Crawl Control is designed for use on steep downhill trails when control is the highest priority. It holds back the vehicle, making sure the speed is appropriate to the steepness of the terrain, so all the driver has to do is steer.

The LX suspension supplies a mix of ride quality and cornering capability consistent with other large, multi-passenger luxury vehicles. Some vehicles in this class use air bag suspensions, but in the LX coil springs are used on all four corners, supplemented by an active variable damping system that controls body pitch and dive. The combination is effective. We noticed the LX squats very little upon hard acceleration, the front stays level when we got on the brakes, and in general, the vehicle stayed composed during spirited driving.

The level of damping is selectable. It's possible to select Sport, Normal, and Comfort damping via a switch on the dash, which allowed us to tune ride quality depending on the road surface. We think we would operate on Comfort for highway driving, and Sport if we were faced with a mountain road with a lot of side-to-side transitions. The difference between Normal and Comfort was not apparent to us as we drove, but the difference between Sport and Comfort was definitely discernable.

Unless you drive a truck regularly, parking and maneuvering any big SUV will take some practice. Driving the LX, we found that the hood is tall, making it hard to keep track of the right front corner in particular. Rear visibility is compromised by headrests and sheer height. On the LX, the problem is made easier in two ways. First, steering at slow speeds requires very little effort, and second, visibility is enhanced by new electronic systems.

One such system uses wide-angle cameras located in the front grille and passenger-side mirror to give the driver an enhanced view along the front and side of the vehicle by projecting images of these blind spots on a split-screen display. Another system uses ultrasonic sensors to warn of contact with objects around the front, rear and corners of the vehicle when parking. We found that, with these systems operating simultaneously, even a driver who normally operates a smaller car can park and maneuver the LX in close quarters with accuracy and confidence. They all work together intuitively; it just takes a little patience.

The LX is built with the strong brakes a capable hauler requires. They include large ventilated disc rotors with multi-piston calipers, enhanced by numerous active safety systems. These include Brake Assist (shortening stopping distances in emergencies), all-terrain ABS, and Electronic Brake Force Distribution to balance braking on slippery surfaces.

We towed an 8500-pound trailer for an hour or so with the new LX 570 and found the engine and transmission had no trouble hauling the load up hills, as we expected. The downhill side is often the bigger challenge, as both brakes and transmission are part of what it takes to maintain control. We found that the transmission will downshift on its own, from sixth to fifth gear then to fourth gear, to enhance engine braking and fuel economy. The uphill/downhill shift logic seems flawless, responding to very slight tip-of-the-toe throttle inputs. But for those times when manual control seems called for, there is a sequential shift mode that gives the driver this control.

All Lexus vehicles offer a Pre-Collision System (PCS), including the LX. It's integrated with the optional Dynamic Radar Control, which at $2850 is a fairly pricy option. However, PCS is an innovative safety system that is enabled by the use of radar. With the Pre-Collision System, the car's radar can determine if a crash is unavoidable. If that ever becomes the case, the system tightens up the seatbelt, increases brake sensitivity and applies maximum braking force when the driver touches the brake. By reducing the speed at impact, and positioning the occupants, PCS allows all the other built-in safety systems to work better. According to Lexus engineers, scrubbing off just a little speed at the last second can be enough to save lives. While you don't want to crash at 35 mph, it's better than crashing at 55 mph.