Model Strengths:
As nimble as a much smaller vehicle; available with two powerful gas V8s or a modern diesel; luxurious, reliable, safe, and stylish.

Model Changes:
New for 2008, the GL550 adds Mercedes' impressive 5.5L V8 engine to the GL Class. These vehicles are built alongside-and share many parts with-the M and R Classes. Due in part to its unibody construction, the GL Class offers nearly the same agility as smaller SUVs, only it carries a gigantic 83.3 cubic feet of cargo space. All models feature automatic four-wheel-drive and a smooth seven-speed automatic transmission.

Model Value:
The 2008 GL Class is the large basketball-team-sized SUV in the Mercedes stable, making M-B a serious contender in the full-size luxury sport utility segment. The GL320 CDI has a state-of-the-art diesel engine. Besides offering enormous reserves of torque and making the GL320 CDI one of the only seven-passenger SUVs that can boast a highway fuel economy rating of 24 mpg, it is quiet, doesn't smell, and satisfies emissions requirements. The GL450 V8 is also a remarkable vehicle for family hauling adventures, with loads of luxury features and room, as well as 335 horsepower. But if even that's not enough, the GL550 kicks out 382 horses to drive its massive 21-inch aluminum wheels, and most of the goodies that are optional on the lesser GLs are standard on the GL550.

Model Overview:
For 2007, Mercedes-Benz rounded out their family-oriented array by introducing the seven-seat GL Class, and for 2008 the manufacturer adds the higher-performance GL550 to the lineup, with its 5.5L V8 and 21-inch wheels.The 4.7L V8 found in the GL450 is a derivative of the four-valve-per-cylinder engine that first appeared in the S550. In the GL, it makes 335 horsepower and 339 ft-lbs. of torque. A seven-speed automatic transmission helps the GL450 sprint to 60 mph in only 7.4 seconds.The GL320 CDI starts at $53,000, $2,500 less than the GL450, and was introduced late during the 2007 model year. While it only makes 215 horsepower, the 3.2L V6 diesel engine makes a whopping 398 lb-ft or torque. It will banish all your old ideas of what a diesel engine is like, too: it's quiet, has no noticeable odor, and offers a tidal wave of torque.The GL550, starting at $76,975, improves the powertrain lineup with Mercedes' impressive 5.5L V8. Outside, 21-inch wheels and more aggressive styling for the front grille and fender flares are standard. Rounding out the remainder of the GL550's $21,475 base price differential is much of the GL450's optional equipment list, including trailer stability assist, an adaptive damping system, sunroof, bi-xenon headlights, power liftgate, leather upholstery, heated rear seats, burl walnut trim, the Parktronic system with rearview camera, hand-free communication and voice-recognition capabilities, and more.The interior of all three will look familiar to M Class owners, but there are a few surprises. The middle row of seats is split 60/40, and tumbles on the passenger side for access to the third row. The third row has a reasonable amount of legroom, which makes the GL Class versatile as both a cargo and a people hauler. One of the neatest features on the vehicle is the two buttons in the rear cargo area that raise or lower either third seatback electrically. Total cargo space with both rows folded is a voluminous 83.8 cubic feet.Plenty of protection is built into the GLs. Besides a very strong roll cage body, passive safety items include permanent four-wheel-drive, four-wheel disc brakes with ABS, an electronic stability program, traction control, and eight air bags.The GLs come standard with all the power accessories you'd expect, along with dual-zone automatic air conditioning, a six-disc CD changer and a multi-function leather steering wheel. Bird's-eye maple trim (burl walnut on the GL550), eight-way power and heated front seats and HomeLink add to the SUV's luxurious feel.On the GL320 and GL430, optional rear park assist, running boards, xenon lights, harman/kardon audio, tri-zone climate control, leather seats, and a rear entertainment system ensure that the GL can be configured to just about any taste.Aside from the size of the family the vehicle can accommodate, what separates the GL from the M Class is the air-adjustable suspension. Besides being able to raise and lower the GL, you can also choose between a comfort and sport setting that produces an easily noticeable change in ride. It also automatically levels the front and rear end as the weight of the load varies.