Can the revamped Jeep Grand Cherokee — once apioneer — measure up against its luxury rivals?

The Jeep Grand Cherokee deserves much of the credit — or blame, depending on your view — for transforming an off-road, four-wheel-drive vehicle into an acceptable substitute for a luxury car. The success of the original 1993 Grand Cherokee and its successors proved that suburbia was ready for a tall-riding, four-wheel-drive wagon.

Now DaimlerChrysler is rolling out the third generation of the Grand Cherokee. This time Jeep is playing catch-up in the segment it invented. As new entries muscled into the luxury SUV market, the Grand Cherokee suffered in comparison with smoother-riding rivals. The Jeep brand has long boasted that any Jeep could traverse a brutal off-road desert track called the Rubicon Trail. But the rugged suspension system behind that claim resulted in a less refined ride for the 75 percent or so of Jeep owners who never take their vehicles off pavement.

The 2005 Grand Cherokee aims to fix that rough ride without alienating loyalists who like the Jeep precisely because it isn't as soft as a Lexus.

The new Grand Cherokee's exterior design and its basic fivepassenger package represent the status quo, refined. From 20 paces, the new Grand Cherokee looks a lot like the old one, even though it is 5.3 inches longer and has a longer wheelbase and wider track. The new body has crisper lines, and the front end has adopted the classic Jeep look with round headlights.

Inside, the new Grand Cherokee has an interior that's positioned somewhere between truck and car. Luxury car designers generally strive for a smooth, one-piece look for the dashboard, but the Grand Cherokee's dash looks as if it were pieced together in chunks. Better are the seats, which are comfortable even after hours on the highway.

The most important changes to the new Jeep are under the vehicle. The old model's trail-busting solid front axle has been replaced by an independent front suspension and rack-and-pinion steering. The rear end still rides on a solid axle, but the suspension has been upgraded. The result is that the new Grand Cherokee has less body roll on the freeway and handles more crisply.

I test-drove a Grand Cherokee Limited with a 4.7-liter V-8 engine, which Chrysler says will be the most popular model. Grand Cherokees also come with a new 210-horsepower, 3.7-liter V-6 and an optional 5.7-liter Hemi V-8.

The new Grand Cherokee is not as nimble as a sedan or a light, crossover SUV like the Toyota Highlander. But it rides comfortably and relatively quietly. The 4.7-liter V-8 delivers 230 hp through a fivespeed automatic transmission, which is adequate, but not thrilling.

The least expensive, six-cylinder Grand Cherokee starts at $26,775 including destination charges. My test Jeep, with a base price of $34,690, came loaded with options, including a $1,200 navigation system and the $195 Sirius satellite radio package. Total sticker price was $40,890.

That price puts the Jeep squarely in competition with vehicles like the Lexus RX 330 and the Acura MDX. The new Grand Cherokee is a substantial improvement over its predecessor, and it excels in real off-road work and trailer towing compared with the luxury crossovers. But the MDX, which seats seven people, offers more standard horsepower and better fuel economy (17/23). The five-passenger Lexus has more cargo room (38.3 cubic feet, versus 34.5) behind the rear seats and gets better mileage from its 230-hp V-6. The new Jeep has a hill to climb to measure up to these rivals.