The 2007 Chevrolet Tahoe seemed much more at home out in Arizona, where it could negotiate the open countryside, and you could visualize it towing a big horse trailer, or a house-sized recreation trailer.

The North American automotive media got the chance to first drive the Tahoe in that cactus country setting of Arizona, but we were asked not to reveal our impressions until the world could catch a look at the Tahoe during this past week’s press days at the North American International Auto Show.

Driving through the twisting mountain roads outside Phoenix, or zipping along highways down in the valley, the Tahoe performed admirably.

In fact, it can be unequivocally stated that the 2007 Tahoe is by far the best Tahoe ever built.

It is sleeker, more aerodynamic, with smoother and more appealing edges than the husky but squarish predecessor, and with dozens of fancy creature comforts that are breakthrough items for GM, and even if all or almost all of the features are already out on a variety of competitors, it’s impressive that the Tahoe has packed all of them into its shapelier body.

General Motors is stressing those features, but mostly it’s stressing that the Tahoe has "broken the 20-mile-per-gallon barrier" for large SUVs. There were all sorts of stylish responses to the challenges facing the automotive world at Detroit’s show – small cars, smaller cars, hybrids, and all sorts of compact, downsized and fuel-efficient crossover SUVs.

And there was General Motors, introducing as its primary new vehicles the all-new Chevrolet Tahoe, and the all-new Cadillac Escalade. The corporate twins, are trimmed up with distinctly different features, but they are both large SUVs with big V8 engines.

It’s been eight model years since General Motors made its last major change to its large truck-based vehicles, back when the code-named 800 trucks supplanted the 12-year stand of the 400 model. So the new 900 was long in coming.

"The 400 model was pretty loose," said GM engineering spokesman Gary White. "The 800 was much stiffer, but is still squeaked and rattled more than we liked."

When gas prices rose toward $3 a gallon, people started looking for more fuel-efficient cars. When it looked as though the prices would stay over $2, the exodus from large SUVs left acres of unsold trucks on GM, Ford Toyota, Nissan, and Dodge dealerships, but General Motors sells the most and therefore felt the dropoff the most.

As cars stood unsold, the incentive rebates rose. Edmunds.com, an industry-analyzing website, said that calendar year 2005 ended with large SUVs averaging just over $6,000 per unit, while large trucks averaged $4,049, and nothing else had over a $3,000 average, with midsize SUVs third at just under that mark.

Compact cars, on the other hand, averaged only $876 in rebates per unit, and sports cars only $553. Such small rebates gave large SUVs an inflated popularity, as many buyers couldn’t pass up the bargain price, even knowing fuel economy pains might be forthcoming.

Meanwhile, back at Detroit, virtually all of the top GM competitors were stressing crossover SUVs, particularly Ford, Lincoln, Dodge, Jeep, Hyundai, and Honda, through its Acura arm. Most of those companies also introduced fuel-sipping compact cars and small hatchbacks.

Still, for those who genuinely need a large SUV for hauling a big family around, or towing hefty trailers, SUVs fill an important niche, and they will be around for years to come. And the Tahoe, which ranks as king of the large-SUV hill, was crying out for a renovation.

Aerodynamic smoothness shows up on the flush rear side glass, and on the integrated antenna, and removal of the lip on the fuel-filler door, dropping the coefficient of drag to .363, which is the best for large SUVs.

The front has a stylish upgrade on the grille, with its horizontal headlights and the horizontal line that splits the grille. Great attention to narrowing all body panel gaps adds to the classiness of the Tahoe.

Inside, the headliner is made of a woven fabric that is an improvement over that ubiquitous fuzzy stuff of the past. The front seats are heated and so is the second row of seats, while the rear seat folds and tumbles forward at the push of a button to join the foldable rear seat in making a flat floor. The instrument panel is moved down and positioned six inches forward, to make the roomier interior seem roomier still.

Some other intriguing features include rain-sensing wipers, a rear camera to help avoid crushing smaller vehicles or objects when backing up, and remote start, a feature on other GM products that is eminently useful in cold climates.

Out of view of driver, occupant and passer-by, the Tahoe has been improved from the ground up. It sits on the same wheelbase, but the frame has been strengthened considerably. The entire frame has been increased 49 percent in torsional stiffness. That’s a lot. The new front section, with stronger cross-members, has been increased 90 percent in torsional stiffness.

That allowed engineers to remake the suspension and steering for much better handling feel, from on-center steering to cornering precision without the sway normally associated with large, top-heavy trucks.

A 3-inch wider stance up front aids that feel, and use of higher-strength steel in body pillars adds to the safety of occupants, along with rollover sensors and roof-mounted side airbags, supplementing the usual array of airbags and side pillars.

Under the hood, the 5.3-liter pushrod V8 is all aluminum, with 320 horsepower and 340 foot-pounds of torque, and featuring an imperceptible cutoff of four of the eight cylinders when cruising.

That’s something GM has been promising for two years, while Chrysler beat the General to it and now has it in use on every Hemi V8 application.

I like the instrumentation, and the new seats, which have better side support than the smoothly slippery seats of past Tahoes. Steering feel and the improved brake feel add to the feel of control. The interior room and smoother exterior leads Chevy stalwarts to claim the Tahoe drives smaller on the outside, while you live bigger inside.

The biggest claim for the Tahoe is improved fuel economy. That, too, remains to be seen. All the cars in the introductory fleet had the 5.3 V8, the two-wheel-drive Tahoe EPA estimates are for 22 highway and 16 city, while the four-wheel-drive units show 21 highway and 15 city.

These are EPA estimates, with city figures obtained in a lab without driving, and highway figures calculated without going over 60 miles per hour and without air-conditioning on.

I asked if Chevy had any real-world evidence that they could get that sort of mileage, but Chevrolet officials said they only use the EPA figures.

No matter what the actual mileage comes down to, and even if large-SUV sales drop off from their annual sale of 750,000, GM is not likely to lose their 62-percent share of that market.

GM’s Gary White mentioned that the company likes that 62 percent share, "But with the new Tahoe, we want to take the excuses away from the other 38 percent."