SAN DIEGO – Landlines. Tube TVs. The VCR.

In a world of iPhones, paper-thin LCDs and Hulu, all now are quaint reminders of yesteryear.

As is a big body-on-frame SUV like the Lexus GX.

Once red-hot in the bigger-is-better 1990s, only a scattershot of SUVs still exist in the U.S. auto industry, and few remain in the luxury segment save for fullsize behemoths like the Cadillac Escalade and Lexus LX.

Most SUVs have been furloughed from brand lineups, replaced by sleeker, often smaller and generally more fuel-efficient car-based cross/utility vehicles.

An SUV today, no matter how nice, falls into the category of “best buggy whip” – soon to be irrelevant as technology and tastes march on.

But the ’10 Lexus GX is a very nice buggy nonetheless. Despite its ladder frame and solid rear axle, the third-generation GX’s ride is supple on-road and no more harsh than a Toyota Highlander CUV.

To improve handling, an Adaptive Variable Suspension allows drivers to select a comfort mode. There also are normal and sport settings.

As with similar adjustable suspension systems, such as the one in several Acura CUVs, it is hard to detect a difference between various driving modes on smooth roads.

For off-roading, which Lexus officials say GX owners sometimes do when hauling a boat or trailer, there is the standard Kinetic Dynamic Suspension System, which also was on the previous GX.

KDSS, with new steering and yaw sensors for 2010, effectively disengages the stabilizer bars, which are jointed, through use of a pressure-sensing valve linked to hydraulic cylinders. The setup allows for greater wheel articulation on rugged terrain.

The GX also has full-time 4-wheel-drive with a Torsen torque-sensing center differential that can apportion front-to-rear power to a variety of ratios, depending on driving conditions.

In normal situations, Lexus says 60% of torque is channeled to the rear wheels, while 70% of torque can drive the rear axle in curves. When excessive rear wheel spin is detected, the system employs a 50:50 front/rear split.

Propulsion comes from an all-new 4.6L V-8, replacing the 4.7L V-8 in the ’09 GX 470.

Despite its smaller size, the 4.6L, also in the Toyota Tundra fullsize pickup truck, produces more horsepower and torque than the old 4.7L.

The new powerplant, all-aluminum with dual variable valve timing, returns commendable fuel economy – for a V-8.

In one 21-mile (34-km) mixed-driving trek, the GX averages 18.6 mpg (12.6 L/100 km). Some V-6 sedans can barely muster that.

’10 Lexus GX 460
Vehicle type Front-engine, rear-wheel-drive, 4-door SUV
Engine 4.6L DOHC V-8 with aluminum block/heads
Power (SAE net) 301 hp @ 5,500 rpm
Torque 329 lb.-ft. (446 Nm) @ 3,500 rpm
Bore x stroke (mm) 93 x 84
Compression ratio 10.2:1
Transmission 6-speed automatic with sequential shift
Wheelbase 109.8 ins. (279 cm)
Overall length 189.2 ins. (481 cm)
Overall width 74.2 ins. (188 cm)
Overall height 72.2-74.2 ins. (183-188 cm)
Curb weight 5,305 lbs. (2,406 kg)
Base price $51,970-$56,675
Fuel economy 15/20 mpg city/highway (15.7/11.8 L/100 km)
Competition Land Rover LR4, Range Rover Sport, Mercedes Benz G-Class, Hummer H3
Pros Cons
Decent fuel economy Sluggish acceleration
Comfortable ride Light steering off-road
Slick interior Some misaligned panels

A longer route, which includes some extensive off-roading at a local ranch, averages 17.6 mpg (13.4 L/100 km).

The first non-hybrid application of Toyota’s cooled exhaust-gas recirculation system, which introduces cooled exhaust gases into the intake manifold, helps improve fuel economy, Lexus says.

A 6-speed automatic transmission also boosts fuel economy and fits in the same space as the GX 470’s 5-speed gearbox but has a higher top gear ratio.

At low speeds, such as off-road, the rack-and-pinion power steering is uncomfortably light. Firmer steering would be better under those conditions.

Other complaints are minor: Throttle tip-in could be more aggressive (Toyota seems to err on the side of “floor it!” with its trucks); headroom in the otherwise roomy third row is limited; and misaligned panels around the glove box mar one pre-production test vehicle.

Interior surfaces largely are well done though, with an attractive matte metallic finish on some panels and just-right levels of Lexus’ signature glossy wood trim.

The headliner is a suede-like fabric with an upscale feel that is not too rubbery.

It’s difficult to make a large vehicle attractive because interior space demands dictate squarish proportions. Embrace the box, we say. The GX’s rounded, sloping nose is out of whack with the rest of the vehicle and more suited to a lower-profile CUV.

As a luxury vehicle, the GX is loaded with amenities, many of them standard.

There is no extra charge for heated and ventilated front seats, making the vehicle equally appealing in warm and cold climates. Also, there is a memory system for the driver’s seat, steering wheel and exterior mirrors. The third-row seat has standard power and folds flat.

A 9-speaker audio system with Bluetooth connectivity, iPod auxiliary jack and XM satellite radio receiver is included, as is a rear back-up camera that projects an image on a 4.2-in. LCD display.

The Convenience package is available with power retracting auto-dimming exterior mirrors, while the Comfort Plus option includes heated second-row outboard seats.

Stand-alone options include a hard disk-drive navigation system with casual-speech voice recognition and premium Mark Levinson-brand audio system with a whopping 17 speakers.

Standard safety features include 10 airbags, electronic stability control and brake assist.

Optional are two versions of a collision-prevention system, one basic with dynamic radar cruise control and the other with a driver-attention monitor and lane-departure alert.

The monitor uses a camera mounted on the dash to detect whether a driver’s face is focused forward. If it is not for more than a few seconds, and an object is detected in the path ahead, sound and light alert the driver. If no action is taken, the pre-collision system “gently” applies the brakes.

The ’10 GX begins at $51,970 for a base grade and $56,675 for premium trim. Destination and handling is an additional $875.

Overall, it is a good vehicle despite some minor issues. But even Lexus officials seem to recognize the GX’s days are numbered, at least as a body-on-frame architecture.

Lexus General Manager Mark Templin recently suggested the vehicle could migrate to a unibody platform. Such a move likely would increase sales and interest.

The business case for a switch is obvious: Sales in the Ward’s Luxury Middle CUV segment declined just 0.1% last year, while Luxury Middle SUVs tumbled 46.3%.

Albeit a segment-leading number and improvement over 2009’s 6,235 units, Lexus predicts 14,000 GX sales in 2010.

cschweinsberg@wardsauto.com