The 2008 HUMMER H3 offers a choice of engines, but with either, lousy fuel economy clouds its otherwise competent on-road handling and truly impressive off-road capability.
MyRide.com elaborates on what's under the hood, noting the base model HUMMER H3 2008 contains a "3.7-liter five-cylinder engine that offers 242 horses and 242 lb.-ft of torque," while the H3 Alpha has a "5.3-liter, 16-valve aluminum engine pushing 300 horsepower at 5,200 rpm and 320 lb.-ft of torque at 4,000 rpm."
For city driving, says Edmunds, the 2008 HUMMER H3 has "sufficient punch to handle the cut and thrust"; however, when faced with inclines and merging on the freeway, it grows a little "winded." At 4,700 pounds, the HUMMER H3 is missing the power to pull the weight. Motor Trend feels “the I-5 is just adequate for on-road driving in five-speed manual form and is just plain anemic when equipped with the four-speed auto, especially in urban running.” In the V-8 version, Cars.com notes, “Hummer says the Alpha can accelerate from zero to 60 mph in about 8 seconds, which isn't bad when you consider the SUV's near 5,000-pound curb weight.” Edmunds adds the engine makes it "sound like Bigfoot." Automobile observes, “The new engine's capabilities are even more impressive when you look at the standard H3's barely adequate inline five-cylinder engine, which has been known to frustrate drivers on long ascents and highway on-ramps.”
Cars.com notes that the five-cylinder HUMMER H3 is "the first HUMMER offered with either a manual or an automatic transmission." The Alpha version, Edmunds reports, comes only with a four-speed automatic. A "four-speed automatic transmission works with a full-time four-wheel-drive system," says MyRide.com, "featuring a low range, optional locking rear differential, and the added strength of a cast-iron front differential housing." When all of these components are put together, you end up with "a rig now capable of towing up to 6,000 pounds (the five-cylinder H3 tows up to 4,500 pounds)." Motor Trend explains further: “The four-wheel-drive system itself is full-time, splitting engine torque 60/40 (back to front) during normal pavement conditions, but is able to send as much as 100 percent of available torque to the front or rear wheels when needed.” All H3s have 9.1 inches of ground clearance, and serious off-road performance is also aided by the maximum approach angle of 40 degrees and maximum departure angle of 37 degrees.
Fuel economy is an issue, of course, with the brawny HUMMER H3. Automobile says, “Like all Hummers past and present, the H3 Alpha's V-8 will be criticized for its combined government fuel economy rating of 14 mpg. But there is a bright side; all that extra power comes with only a 1 mpg penalty compared to the significantly weaker in-line five.” The EPA rates the HUMMER H3 at 14/18 mpg with the five-cylinder, and 13/16 mpg for the eight-cylinder. According to ConsumerGuide, the HUMMER H3 2008 "averaged 17.1 mpg in a mix of city/highway driving"; however, the Alpha trim level "averaged 13.1 mpg in city driving."
Gas guzzler or not, the HUMMER H3 handles well. Edmunds says the HUMMER H3 2008 has "serious off-road ability" and provides a "smooth ride on pavement" along with stable handling. “While there's no hiding its considerable curb weight in the corners it feels surprisingly stable, with predictable body roll,” they report. Even so, MyRide.com notes the "On-road ride is harsh." ConsumerGuide points out the "H3 is prone to bobbing at high speed," but it is "reasonably agile with no excessive body lead in turns." The steering is "responsive," though some testers experienced "mushy brake pedal action." However, “off-road, it really shines,” Automobile observes, “Its feel is certainly less truck-like and more comfortable than the uplevel H2, making it a fine choice for hauling kids, cargo, or going off on weekend road trips.”