2007 Hummer H2 Performance Review [ 2008 ]
Hummer H2 Performance Review
Performance - 7.9 (Good)
The 2007 Hummer H2 offers on-road performance that is on par with other full-size, truck-based SUVs, and off-road performance that has few equals. Edmunds test drivers find that, "Despite its penchant for mud bogs and boulder trails, the H2 still maintains a commendable demeanor on the open road."
MSN adds that "the H2 would be comfortable during a cross-country trip and isn't difficult to drive in congested traffic, as long as its driver keeps in mind that it is very big, high and extremely wide."
The Hummer H2 offers a pleasant driving experience but never lets the driver forget that it is a large and heavy SUV. Automobile Magazine says the H2's "prime on-road objective was safe and predictable handling" and that "on Utah's scenic byways, the behavior of the giant land crab was both benign and uninspiring." The Flint Journal says "the ride is not Cadillac smooth and it doesn't corner like a Chevy Corvette, but its ride and handling are pretty good for a big four-wheel-drive SUV."
In terms of acceleration, the H2 is again all right, given its size. "On the open road, the H2 moves right along, oblivious to the laws of aerodynamics" says Kelley Blue Book. Forbes reports "passing acceleration isn't electrifying -- but strong enough; getting used to driving the H2 takes no time at all." MSN adds, "The test H2 SUT got up to highway speed steadily and merged into traffic without much fuss, though response to the accelerator was not instantaneous in this 6,400-pound vehicle."
Acceleration and Power
The 2007 Hummer H2 comes standard with a 6.0-liter Vortec V8 engine, producing 320 horsepower and 365 pound-feet of torque. Though the engine is stout and strong, the H2 is heavy. Edmunds says, "The big V8 under the hood provides plenty of pickup in most situations, but the combination of 3 tons of weight and a near total lack of aerodynamics renders the H2 sluggish at highway speeds." Motor Trend puts the H2's engine performance in perspective. "Installed in the 6400-lb H2, the engine gives roughly the same weight-to-power ratio as a Toyota Camry four-cylinder. Of course, you could tow two Camrys with an H2, but that's another story." MSN reports that the engine, which uses pushrods instead of camshafts, "is brawny and works with a smooth, responsive 4-speed automatic transmission."
Because of the H2's weight, it is exempt from EPA fuel economy estimates. As the Flint Journal notes, however, "You cannot expect good mileage from a vehicle that weighs more than 3 tons." In many test drives, reviewers noted average gas mileage as low as 10 miles to the gallon or worse. While many Hummer buyers, and large SUV buyers in general, may not have gas mileage as a primary concern, MSN notes, "in contrast, the 2005 Cadillac Escalade EXT -- another five-passenger SUV with a pickup bed at the back, a 345-horsepower, high-output version of the Vortec 6000 V8 under the hood and which weighs some 500 less than the heavy-duty H2 SUT--is rated at 13 mpg in the city and 17 mpg on the highway." In short, the Hummer H2 has poor fuel economy, even for a full-size SUV.
Mated to the V8 is a four-speed automatic transmission, which most reviewers felt ably translated the engine's power to the road. The transmission works with a Borg-Warner 44-84 transfer case with a 40/60 front/rear torque bias. Automobile.com says the H2's "heavy-duty 4-speed automatic transmission seems perfectly suited to the job at hand, downshifting when needed and upshifting without hesitation." Still, Forbes said they'd "appreciate an overdrive lockout to enable quicker downshifts for passing."
Handling and Braking
Despite its truck background, the H2 provides a comfortable on-road ride. "H2's ride doesn't beat you up," says Motor Trend, and Motor Week says, "In terms of comfort, it's right on par with the GMC Yukon Denali." Cars.com adds, "Far more civilized than the H1, the H2 driving experience is like that of other large SUVs."
The reason the H2 has such a surprisingly comfortable ride for a heavy, off-road vehicle is its suspension. "Progressive-rate rear coil springs and high-pressure gas monotube shocks take much of the credit here," says Motor Trend. The standard suspension in the front is an independent setup with torsion bars, 46-mm monotube gas-charged shocks and a 36-mm stabilizer bar. Standard rear suspension is a five-link variable coil spring setup with 46-mm monotube gas-charged shocks and a 30-mm stabilizer bar. Though the standard suspension shares many components with GM trucks, Edmunds notes that "key suspension components were beefed up to handle the additional demands of severe off-road duty, while a special frame design in front isolates the front axle for less vibration and noise in the cabin."
The H2 steering is also fine for its size. " It ain't light on its feet!" says Motor Week, adding, "But steering feel from the variable ratio, recirculating ball steering unit is light and progressive with a good deal of feedback." Still, the H2 isn't perfect. "It can be difficult to park, and driver visibility is not the greatest," reports the Flint Journal. MSN also found the H2 difficult to maneuver in small spaces. "I found myself needing to back up, pull forward, and repeat, in order to get maneuvered out of a tight turn off-road," it says.
On the road, Automobile Magazine notes that "although the H2 doesn't fall apart when pushed, it understeers clumsily at the limit despite a 40/60 percent front/rear torque split, and its brakes fade quickly. Body roll is, as you might expect, significant." Automobile.com summed up problems with the H2 on-road, saying, "If you're looking for Acura MDX or BMW X5 handling keep driving."
When a vehicle weighs 6,400 pounds, it has to have good stopping power, and the 2007 Hummer H2 doesn't disappoint. Four-wheel disc four-channel anti-lock brakes and dual piston calipers with dynamic rear proportioning stop the H2. The H2 also uses engine braking to minimize brake fade, much like giant tractor-trailer trucks. Auto Mall USA notes, "Even when soaking wet, these brakes performed flawlessly, with lots of pedal feedback." Motor Week took the H2 on a track and noticed that "Stability is excellent, but after several runs, brake fade was quite noticeable." Since most people won't be taking their H2s for several timed laps at a track, this most likely won't be an everyday concern. For daily driving, Edmunds says, "the H2's large four-wheel discs provide plenty of power and a decent pedal feel."
Off-Roading
Though most reviewers think the majority of H2 buyers will never take the SUV off-road, they also agree that off-road is one area where the H2 really shines. Edmunds says, "It almost goes without saying, but the H2 borders on unstoppable offroad," and Autofieldguide.com adds, "The H2 eats rocks."
The H2 is such a strong off-road performer in part because of its military heritage (the H2 is based on the H1, which is a civilian version of the military's Humvee). The H2 follows in the Humvee's footsteps by arriving off-road with a full complement of rock-solid off-road components. Passengers are kept safe from the elements, and the H2 is kept in one piece, thanks to a welded, two-sided galvanized steel body. To avoid damaging key parts of the undercarriage, all components on the chassis are even with or above the frame rails. Further protecting the H2's underbody are its 9.4 inches of ground clearance and skid plates. The H2 is also designed with steep approach and departure angles.
The only problem with the H2's design when off-road is poor visibility. A small, nearly upright windshield and small windows, coupled with a wide body, make a spotter a key accessory for tough rock crawling, many reviewers noted.
Along with the overall body and chassis design, the H2 brings excellent mechanical off-road equipment to the trail. The four-wheel-drive system has a setting for every off-road situation. 4 Hi Locked or 4 Low Locked sends equal power to the front and rear wheels, and the driver can choose to lock the rear wheels in a 50/50 power split. 4 Lo Locked is the preferred setting for slow rock crawling, providing maximum grip and low-range torque. Low-speed traction control (activated or deactivated at the push of a button) allows drivers to have controlled wheelspin to work its way through soft sand without losing stability and allows the H2 to soldier on even if only a single wheel has traction. The optional air suspension allows drivers to raise the SUV for additional ground clearance. Thanks to these systems, says Automobile Magazine, "Despite its considerable weight, width, and length, a standard-issue H2 can keep up with Rubicon-ready Jeep Wranglers and Land Rover Defenders, which is no small accomplishment."
The H2's suspension and tires also work hard off-road. The independent suspension in the front and five-link variable rate coil spring setup in the rear (both with 46-mm monotube gas-charged shocks and stabilizer bars) allow for maximum wheel articulation for the all-terrain LT315/OR17 tires. The tires were a particular favorite of reviewers, who found that they could climb up to 20 inches of vertical rock face with their impressive grip. MSN reports that "the test vehicle was so unperturbed by steep climbs up and down rock faces, I felt mostly like I was out for a slow Sunday drive."
