THE PRESIDENT IS

warning about our "addiction to oil." And carmakers keep rolling out huge sport-utility vehicles. This may seem thick-witted, but decisions to make this the year of the Big Unit were made four or five years ago.

The industry reckons large-SUV sales are headed down to around 700,000 a year from the peak of about one million earlier this decade. But 700,000 full-size SUVs a year is nothing to sneer at. Automakers believe the pastimes of many Americans say, recreation involving trailers or hauling a boat demand a large SUV.

I test-drove four of them just as gas prices were starting to accelerate this spring. (GM is now offering zero-percent financing on 2006 models of some SUVs. If sales slow enough, more incentives may lie ahead.)

2006 Jeep Commander
The Commander is a new entry from DaimlerChrysler that tries to bridge the full-size and midsize segments. It's not as large as a full-size SUV, but it offers three rows of seats, a high seating position and a V-8. The price tag is in the same class as the big boys, with base prices ranging from $28,235 to $39,100 for a Limited four-wheel-drive model.

The exterior is a throwback to boxy Jeeps of the past. Inside, the Commander has a split personality. The dashboard has a rugged look, but the center console has wood-grain trim. My test vehicle, a Limited, had leather seats that were comfortable in the front row. But the second row felt hard, and the third-row seats were stiff and cramped. On the road, the Commander was well behaved, yet the power steering felt numb.

It ranks fourth for two reasons. First is mileage. Its 235-hp, 4.7-liter V-8 has lower-rated gas mileage 14 mpg city, 19 highway than the more powerful Chevy Tahoe. Second, the interior doesn't work. Not only are the third-row seats hard, but when they are up, they block much of the view out the rear. The load space behind the third row is a laughably narrow sliver.

2006 Nissan Armada
The Nissan Armada is one imposing truck. It's over 17 feet long longest of this quartet. It can tow 9,000 pounds. It's got the biggest V-8, at 5.6 liters, and the second most power, at 305 horses. Behind the wheel, you'll feel like Fred Flintstone aboard a brontosaurus.

There's plenty of room in the first two rows. A rangefinder and rear backup camera help you guide the Armada's ample derriere away from obstacles like VW Beetles or small children. On the road, the Armada felt the most ship-like of these four vehicles.

Its biggest demerit, consigning it to third place, is gas mileage, which at 13 mpg city and 18 highway is poor even by the standards of this class. Armadas start at $35,405. My well-loaded test vehicle had a sticker of $48,655.

2006 Toyota Sequoia
Toyota gets a lot of good press for its Prius gas-electric hybrid. If that car represents corporate superego, the Sequoia is Toyota's id: an All-American big SUV, complete with an EPA highway-mileage rating of just 17 mpg. City mileage is rated at 15 mpg, tied with the Chevy Tahoe.

Toyota did improve on the Detroit formula. The Sequoia's 273-hp, 4.7-liter V-8 runs as smoothly as a big luxury-car engine. Power goes through a five-speed automatic. The Sequoia is relatively quiet on the road.

Sequoias start at $33,425. My test vehicle, a Limited, had a base price of $45,915. Options bulked the sticker to $51,973. The Sequoia ranks second for its interior quiet and decent mileage.

2007 Chevrolet Tahoe
The Chevrolet Tahoe LT that I drove is one of the first of GM's wave of redesigned full-size SUVs rolling out this year. Although the exterior styling changes are subtle, GM has reengineered these trucks extensively where it counts.

Tahoes start at $33,990. My test LT model had a base price of $37,665, but then there were many extras, including the navigation system and XM Satellite Radio. Bottom line, after a total of $12,245 in add-ons: $49,910.

2007 Chevrolet Tahoe

Base Price: $37,665 (incl. destination charge)

Engine: 5.3-liter V-8, 320 hp

Ride/Handling:

Int./Ext. Design:

Comfort/Utility:

Overall Rating:

Comments: Fuel economy leads the field, interior much improved.

The new Tahoe benefits from GM's recent push to upgrade its interior design. The old Tahoe had a boxy dashboard fit for the farm. The new look is more urbane.

The Tahoe is surprisingly agile for a 5,537-pound truck. The 39-foot turning radius beats the Armada and Sequoia, and GM has tightened the ride.

The third row is cramped. The popular seven-seat Tahoe version is a comfortable way for four people to travel with a bunch of luggage and an 8,200-pound trailer.

The reason the Tahoe is No. 1 in this group is the EPA mileage. The 320-hp, 5.3-liter V-8 is rated at 15 mpg city and 21 highway, thanks in part to the "active fuel management" system that shuts down four of the cylinders during highway cruising. That's best in class, and it's done despite a relatively old-tech four-speed automatic transmission. GM plans to offer a six-speed automatic transmission that should further improve mileage.