Mercedes-Benz G-Class Performance
The 2008 Mercedes G-Class is a tough off-road vehicle that can go just about anywhere an SUV can go, but is awkward to drive on the highway, with a bouncy ride and sluggish acceleration on the base model. As a result, it gets one of the worst performance scores in the class.
The G-Class, an off-road vehicle with a long history of military use, is widely praised by reviewers for what Edmunds refers to as its "go-anywhere capability", though few critics identify it as a good choice for an on-road luxury SUV for around town. "The G-Class is a truck-based SUV designed for military activities," says Edmunds, "and it drives like it."
Both the base 5.0-liter engine and the optional 5.5-liter engine receive wide praise, as do the seven- and five-speed transmissions on the G500 and G55, respectively. However, critics are far less impressed by the G-Class's handling on the highway, noting that its firm suspension, tuned for crawling through the wilderness, makes the ride "bouncy," according to MSN. Several reviewers also note that, despite its powerful engines, it's slow to accelerate. In the words of Cars.com, the G "is defiantly truck-like, and it emits a degree of sluggishness and plenty of sound while accelerating." Reviewers criticize the G-Class's boxy shape for its pronounced air resistance and body roll.
Acceleration and Power
The 2008 Mercedes G500 comes with a powerful 5.0-liter 292 horsepower eight-cylinder engine. The G55 comes with an even more powerful 5.5-liter 493-horsepower supercharged eight-cylinder engine. Most critics agree with Edmunds that these "modern V8 engines move the G-wagen with impressive force." However, while these engines are ideal for off-roading, several writers notice that the heavy (5545 pounds) G-Class SUVs equipped with the base engine are relatively slow to accelerate on the open road. "Acceleration is strong," according to Kelley Blue Book, "but falls off somewhat at highway speeds." Several reviewers also note that freeway driving requires constant -- and somewhat exhausting -- pressure on the gas pedal. "The gas pedal also requires too much effort," says Edmunds, "making cruise control a frequent friend on highway journeys." But they add that "the Mercedes-Benz G-Class is surprisingly quiet on such journeys despite having the aerodynamic attributes of a shipping crate." adds reassuringly that "as long as you're willing to get vicious with the gas pedal, though, the G-mobile is strong." In fact, it's strong enough, according to Mercedes, to tow 7,000 pounds using the optional towing hitch.
The G500 comes with a new driver-adaptive electronic seven-speed automatic transmission that Consumer Guide calls "smooth" and "quick-shifting." The optional high-performance G55 retains its five-speed automatic transmission. According to MSN, "the five-speed automatic transmission up-shifts fairly smoothly and downshifts quickly." Both transmissions have Touch Shift control, so that they can also be shifted manually, without a clutch.
Fuel economy is not the G-Class's strong point. MSN goes so far as to call it "pitiful." The G500 has an Environmental Protection Agency rating of 12 miles per gallon in the city and 15 mpg on the highway, while the G55 is rated at 11 city/13 highway. As Consumer Guide points out, "Both models require premium fuel -- and plenty of it."
Handling and Braking
Reviewers are less than thrilled with the way that the G-Class handles on the highway. Cars.com points out that the G Class's strong off-roading capability "detracts from its prowess and pleasure on ordinary paved surfaces." As a result, Consumer Guide says handling "is disappointingly trucky and old-fashioned." Car and Driver echoes this sentiment when they say that "driving this big truck is like driving a house." And feels that "steering is slow and stiff and heavy feeling. Parking the G-class, or guiding it through the shopping-cart assault at the mall, will be hard work." But Forbes sounds a more upbeat note: "The surprising thing about the G500 is that it's so easy to drive. In fact, with a tight turning radius for mall parking-lot maneuvers and excellent mid-range torque from the S-Class-derived five-liter V-8, it's an absolute pleasure to drive a lot of the time."
One reason for the unimpressive handling is the G-Class's tall, boxy shape, which gives it a poor aerodynamic profile and significant body roll. MSN calls the G-Class "a big, decidedly unaerodynamic box that has to punch a big hole in the air." Consumer Guide notes that "even moderately gusty crosswinds cause noticeable wander at highway speeds" and Forbes warns that "if you have to cross the Continental Divide or any other wind-prone region regularly, we doubt you'll be happy in a G-wagen." Another problem for highway drivers is the G-Class's front and rear solid-axle suspension, which is tuned for off-road driving. Edmunds suggests that the suspension "is better suited for off-roading up a hill, not cruising through Beverly Hills." Consumer Guide calls the ride "jiggly," while MSN notes that "the ride can be bouncy over road bumps-on and off road." The critic then recalls, "I felt jostled even going over some manhole covers at city speeds, and the vehicle bobbed up and down on some road expansion cracks on the freeway."
Both G-Class models come standard with a permanently engaged four-wheel drive that has a 50/50 front/rear torque split and electromechanically locking center, rear and front differentials. The 2008 G500 has dual-circuit power-assisted four-wheel disc brakes, with ventilated discs in front and solid discs in the rear. The G55 has internally ventilated disc brakes in front and rear. MSN found that "the brake pedal has a nice progressive action." Both vehicles have an anti-lock brake system with Electronic Brake Force Distribution (EBS) and Brake Assist for automatic braking during panic stops.
There is wide agreement among automotive critics that off-road driving is where the G-Class excels. Cars.com says that it has "serious offroad capability," Car and Driver finds that it "will go places others can't." goes so far as to say that the G Class "is strictly a niche vehicle, with the niche being a hardcore off-road enthusiast with money... The Mercedes-Benz G500 was purpose-built to appeal to a narrow range of buyers ... those who aren't obsessed with aerodynamic styling and actually intend to drive it where fishing streams are more prevalent than road signs."
Several features give the G Class its off-roading abilities. The G500 can generate 336 pound-feet of torque while the G55 can generate 516 pound-feet of torque, which not only gives these two heavy vehicles strong acceleration off the starting line but a strong ability to crawl over boulders. "And that max torque number is laid down in the lowly 2,200 revolutions-per-minute range and carries through up to 4,000 rpm," says The, adding, "Very nice on a four-wheel drive SUV constructed with off-road emphasis." The G-Class also has a high ground clearance, and three lockable differentials to help the vehicle through situations where traction is low and the wheels start to slip - a differential setup not offered on any other production SUV in North America.