If gas were still a nickel a gallon, the Big Three would still be the world s dominant car makers and the majority of Americans would be happily tooling around in big sport utility vehicles [SUVs) like the Chevrolet Suburban. But it doesn t and we don t--which is too bad because the Suburban is actually a hell of a vehicle.

The Suburban has been around in one form or another since 1935, and after having been a hot seller for most of the last decade, sales for 2006 were down by nearly 10,000 to just over 77,000, for an 11% drop year-over-year. Of course SUV sales, especially for behemoths like the Suburban, have suffered across the board. The equally large Ford (F) Expedition is in even worse shape, slipping nearly 23%, and DaimlerChrysler s (DCX) Dodge Durango posted a dismal 39% drop.

Sales are finally beginning to perk up, but the summer driving season is almost upon us, and with it the inevitable higher prices for summer gas. General Motors (GM) reported that sales for the Suburban actually rose 10% for the first two months of 2007 over the same period last year as gas-shy consumers returned to the showrooms. It is more than just lower gas prices that are behind this modest increase: Many dealers are offering customer rebates and bonus cash that could knock $3,000 or more off the sticker.

But it will be a long time before the Suburban will be able to return to its glory days. As of Mar. 1 this year Chevy had managed to sell 11,388 Suburbans. Five years ago, Chevy had sold more than 22,100 by the end of the same period. But even in 2005, before the price of gas spiked, the appetite for Suburbans seemed to be drying up, as the company was only able to sell a feeble 10,562 for the first two months of the year.

One of the reasons is that success breeds imitation and the Suburban, originally introduced in the 1930s, is the granddaddy of big SUVs. Not only has Ford (F) rolled out its own leviathans--the mammoth Excursion was too big and was killed because, in spite of what some people think, even Americans know when to draw the line--but also GM cannibalized some of its own market by creating the GMC Yukon on the same platform, and the smaller, more upscale, and extremely successful Cadillac Escalade [see BusinessWeek.com, 11/2/06, "Cadillac s Crown Jewel "].

Even the Japanese were getting in on the act by introducing the Lexus LX 470 from Toyota s (TM) luxury division and the Nissan (NSANY) Armada, although none of these could contend with the Suburban in terms of sheer size and weight.

The other reason is that even if fuel prices were not a concern, there just aren t that many people out there who would want, let alone feel comfortable driving, a vehicle that weighs around 6,000 pounds and is 18-and-a-half feet long. Little old ladies, urbanites, and single people may find this much heft unnecessary, if not intimidating.

But for those who not only need, but truly want, this much of everything--be they large families, general contractors, or Secret Service details--it would be hard to find a vehicle that is more comfortable, practical, and passenger-friendly. To find out why, read on.

When the 2007 Chevy Suburban LTZ 4WD was delivered to my garage, I must admit I was pretty psyched. I had to drive from Manhattan to Washington, D.C., and while the thought of how much money I was going to have to feed into the gas tank was a little depressing, having so much room for my family for the five-hour trip more than compensated. Also I must confess that as I am over six feet tall, knowing that I would be making the drive in a vehicle that didn t give me deep-vein thrombosis after a few hours on the road was also a relief.

I last test-drove a Suburban four years ago, when they were as common on the road as golden retrievers in Connecticut. And while I was pleased with the 2002 model, the 2007 is light years beyond it in terms of technology, design, performance, and fuel economy.

One of the first impressions that I had on entering the 2007 version was that it was much more refined. The generous space was still there, but I didn t feel this time as though it had been cobbled together from the GM spare-parts bin. And while it feels more luxurious than previous incarnations, it is also still family-friendly. There are lots of storage bins and cupholders. If a French fry gets ground into the carpet, or a little apple juice gets spilled on the seats, there s no cause for panic. The stains can be easily cleaned up. Of course, because there is so much room it is easier for parents to lean over and pluck up an offending Cheerio or attack a spill with a handy paper towel.

How much room exactly? The 07 Suburban comes with standard seating for seven passengers, optional seating for eight and for as many as nine in the LS 1500 and LS 2500 models. Front legroom is 41.3 in. and the rear offers 39.5 in. The third row is somewhat more cramped, though relatively sumptuous compared to most competitors. But where the Suburban really makes sense is in the cargo area.

Too often buyers have to choose between a third row and interior cargo room. Not with the Suburban. It offers the ability to carry a full passenger load and still cram plenty of luggage in the back. In smaller SUVs, when the third row is in use, the only place to put the bags is on the roof.

But there is much more to love about the Suburban. The redesign incorporates a rethink of the dashboard and gauges too, which are just as readable as ever although they look better now. And like so many other cars and trucks this year, a new emphasis has been placed on interior quietness. Thanks to new door seals, headliner, and better overall fit and finish, the Suburban feels less truck-like than before.

The options make the Suburban more deluxe than ever too. These include rear-seat entertainment system with a larger 8-in. screen, an excellent touch-screen satellite navigation system, and a rearview camera system [which is very useful, given the challenges of parallel parking an 18-and-a-half-foot long SUV]. These extras don t come cheap though--and can jack the top-of-the-line LTZ 4WD model, which has a MSRP of around $48,000, well over the $50,000 mark. The less expensive trims, the two-wheel-drive LS and LT, start around $36,860 and $37,635, respectively. [The four-wheel-drive versions start around $3,000 more.]

The improvements to the Suburban were not confined to the interior redesign. Also new for the 2007 is a fully boxed frame for better handling and suspension, as well wider front and rear tracks, new front shocks, and rack-and-pinion steering. All models come standard with automatic transmission and a 5.3 liter V8 engine, which offers 310 horses and 335 foot-pounds of torque.

For more power there is the six liter, 366 horsepower V8, which has 380 foot-pounds of torque. The latter is especially helpful for towing heavy loads. Max towing capacity is 9,700 lbs. for the LT3 2500 two-wheel-drive model, but even the basic model has a standard towing capacity of 7,000 lbs.

On the road, thanks to the new rack-and-pinion steering, the Suburban is less of a beast to drive. Acceleration is pretty good given the fact that the vehicle weighs around 6,000 lbs. But where the Suburban really impresses is with its gas mileage. According to the Environmental Protection Agency, the 5.3 liter 2WD model averages 15 miles in the city and 21 on the highway, which is comparable to the smaller Ford Explorer. [Using ethanol, the Suburban does even better.]

Not so long ago a friend of mine was wrestling with buying a new car. His wife had just given birth to their third child and he knew that his choices were limited. He needed more space, and it boiled down to either a minivan or an SUV. Most wagons just wouldn t cut it size-wise, especially if they also had to bring along a nanny--especially as his older children got bigger. So after looking at smaller SUVs such as the Acura MDX [see BusinessWeek.com, 2/13/07, "Acura s Excellent MDX "], the Mercedes-Benz M Class, the BMW X5, the Explorer [see BusinessWeek.com, 9/1/06, "Ford s Explorer Loses Its Way "] and a slew of others, he settled on the Suburban. When asked what made him choose it he said that nothing even came close in terms of size or comfort. Better yet, to sweeten the pot, the dealer threw in a bunch of discounts and options.

Many potential buyers are feeling the same way. While some opt for smaller or more fuel-efficient cars, others don t have a choice. They have either a big family or a job that requires them to drive a large, CO2-emitting, money-burning SUV or truck. So even if these are people who would like to own a hybrid, it wouldn t be appropriate to their needs.

The problem is that Detroit, or anyone else for that matter, doesn t offer a large people-mover with good fuel economy. Even the rare diesel- or ethanol-burning vehicles and hybrids out there--General Motors offers a hybrid GMC Sierra and Chevy Silverado--are still very limited in availability and none come close to offering the passenger room of the Suburban. In fact, there are probably plenty of potential buyers out there who would love to own a Suburban hybrid, but it doesn t exist yet.

Until that time, if you re in the market for a big SUV, the Chevy Suburban is pretty hard to beat.

To see more of the 2007 Chevy Suburban, click here for the slide show.