2008 Mercedes-Benz GL-Class (GL320 CDI, GL450, GL550)

Initially designed to replace the boxy, dated, but still rugged G-Class sports utility vehicles, the Mercedes-Benz GL-Class takes on an entirely different role in the Mercedes-Benz lineup by taking on the Cadillac Escalade, Audi Q7 and Lexus GX470.

The GL-Class is essentially a stretched and somewhat squared off version of the smaller ML-Class vehicles. They share the ML's fully independent suspension, unibody construction and some powertrain choices.

Standard on the GL320 CDI is a 3.2 liter turbodiesel V6 engine that puts out 215 horsepower and an impressive 398 lb-ft. of torque, the highest of any GL model. Though not certified for sale in states that follow California or Northeast emissions rules in the United States, the GL320 CDI is available elsewhere, where buyers will discover 24 mile-per-gallon fuel economy on the highway and effortless power around town. That performance is due in part to a seven-speed automatic transmission, which is standard on all GL-Class models.

At $2,500 higher than the GL320 CDI's base price of $54,225 is the GL450. Motivated by a 4.7 liter, 335 horsepower, 339 lb-ft. of torque V8, the GL450 is otherwise identical to its diesel brother.

Topping the range is the new-for-2008 GL550, which features a 382 horsepower, 5.5 liter V8. Though its 391 lb-ft. of torque isn't quite up to the GL320 CDI standards, the GL550 moves with authority at all speeds. Both the GL450 and GL550 are rated at 13 and 17 mpg in the city and highway, according to the EPA.

With three rows of passenger seats as standard, the GL is capable of seating up to seven passengers. Standard features on all models include power, heated leather seats, wood trim, a CD changer and automatic climate control. The GL320 CDI and GL450 feature 18' wheels, though 19' wheels are an option.

For the GL320 CDI and GL450, major options include a harman/kardon audio system, xenon headlamps, a heated steering wheel and rear seats, and a premium package with front-and-rear obstacle detection, navigation, power telescoping steering wheel, memory seats and mirrors and a power liftgate. A sunroof and full leather upholstery are also available. Making the GL more capable when the pavement ends is an Off-Road package, which includes a two speed transfer case, locking center and rear differentials, a roof rack, skidplates and a height-adjustable air suspension.

The GL550 adds 21' wheels, special running boards and nearly all of the available features as standard to the mix. The only factory options on the GL550 of note include KeylessGo and a rear seat entertainment system.