Mercedes-Benz launched the GL-Class sport-utility vehicle as a 2007 model, with a 4.5-liter V-8 engine, seven-speed automatic transmission, and seven-passenger seating. Related to the German automaker's five-passenger ML-Class SUV, the new full-size GL-Class model was longer and some 500 pounds heavier, with standard all-wheel drive.
A GL320 CDI edition with a diesel V-6 engine joined during 2007, promising significantly better fuel economy. Mercedes-Benz claims the GL320 CDI delivers the fuel economhy of a four-cylinder engine, coupled with the torque output of a V-8. Though the diesel V-6 produces a modest 215 horsepower, it delivers a 398 pound-feet wallop of torque. Mercedes-Benz says it has a cruising range of 600 miles at highway speeds.
For 2008, Mercedes-Benz has taken a different tack, unveiling a super-potent variation of the GL-Class. Dubbed GL550, the new model contains a 5.5-liter V-8, borrowed from the company's passenger cars. This all-aluminum engine generates 382 horsepower and 391 pound-feet of torque, turning the GL-Class into a performance-oriented machine with ambitious off-road capabilities.
Nearly every previous option has been made standard on the GL550, which rides on 21-inch AMG wheels with all-season tires. Styling touches include flared fenders, a steeply-angle windshield and quadruple exhaust outlets, along with chrome roof rails. Running boards are standard.
Genuine wood trim decorates the GL550's interior, which contains eight-way power front seats. A stationary rear sunroof sits above the third-row seats, which can be stowed by pushing a button.
Standard safety features include electronic stability control, two-stage adaptive front airbags, door-mounted side-impact airbags, and curtain-type airbags with rollover sensing.
Like some other Mercedes-Benz models, the GL-Class exhibits a defiantly heavy feel, but one that's rock solid. In some ways, one might even say that the GL550 drives rather like a rock. All that engine power is needed largely because this SUV feels so heavy - as if it's nearly always pulling hard. As a result, however, performance is brisker than some might expect.
Handling is just a bit on the cumbersome side, on the whole - comparable to most SUVs and better than some. The suspension is definitely taut, approaching stiff; yet, the GL's ride isn't bad most of the time.
Fuel economy, as expected, qualifies as dismal. As in various Mercedes-Benz vehicles, the control layout leaves something to be desired. Deducing how to use the available navigation system is no easy matter, the electronic gearshift isn't especially helpful, and identification of controls and icons is often obscure. On the other hand, the cruise-control lever isn't quite as annoying as in some Mercedes-Benz models, where it's all too easy to hit inadvertently.
On the plus side, the GL550 is beautifully insulated and supremely quiet. Excellent seats are firm but comfortable, with helpful side bolstering that's short of stern, unlike seats in some European vehicles. Although the GL's dashboard is way too complex for many drivers, others are sure to adore each and every intricacy.
Summing up, in view of the GL550's hefty cost, heaviness, control complexity and gas mileage, it's a difficult SUV to recommend. Nevertheless, if you're willing to pay the price for premium quality, heritage, capability and solidity, the GL is worth a test drive and a close look.
Mercedes-Benz aficionados with bountiful wallets are likely to be happy to put up with a few defects, to get another masterfully-crafted and abundantly powerful example of the marque. To others, who wouldn't be customers in any case, packing so many horses into an SUV is an exercise in excess. Even if everything works well together, all that surplus energy is simply unnecessary for practical motoring. Of course, economy-minded and environmentally-conscious buyers can opt for the GL320 CDI instead, gaining most of the GL's virtues with fewer drawbacks.