2008 HUMMER H3NEW YORK – Offering the towing capability that only a V-8 can, the 2008 H3 Alpha broadens HUMMER’s range of versatile, do-anything and go-anywhere vehicles. HUMMER announced the H3 Alpha at the New York Auto Show; it goes on sale this summer.

The H3 Alpha is the second member of HUMMER’s exclusive Alpha series, representing the pinnacle of performance, both off the road and on it. It comes with a new, 5.3L V-8 engine that delivers 295 horsepower (224 kW)* and 317 lb.-ft. of torque (438 Nm)*. It is partnered with a four-speed automatic transmission and enables a maximum towing capacity of 6,000 pounds (2,721 kg) – an increase of more than 33 percent over other H3 models

H3 Alpha is, simply, the ultimate HUMMER H3,” said Martin Walsh, HUMMER general manager. “It delivers all of H3’s renowned off-road capability, but with enhanced performance that is suited to a variety of lifestyles.

In addition to the V-8 engine, the H3 Alpha also includes the popular “Luxury” equipment package, the Chrome Appearance package, 16-inch chrome wheels, a 4.10 rear axle ratio and special Alpha identification, including a prominent tailgate badge, horn pad badge and embroidered front headrests with the “Alpha” insignia.

For customers who want a more accessorized appearance straight from the factory, the Alpha model can be combined with the H3X content, which includes bright roof crossbows, chrome fuel door, a body-color grille and unique spare tire cover, tires, wheels and center cap, and a brush guard. Additionally, HUMMER Accessories offers an exclusive line of GM-designed, manufactured and validated accessories that are engineered and tested for no-compromises fit, finish and performance.

Because HUMMER stands for more than just off-road performance, the H3 Alpha builds on the style and refinement of the H3 lineup and offers a unique, instantly recognizable statement on the road,” said Walsh. “In short, the H3 Alpha matches HUMMER’s off-road expectations with on-road attitude.

Alpha – the ultimate HUMMER
2008 HUMMER H3HUMMER Alpha models represent the top in performance, capability and comfort. The H1 Alpha was the first of these ultimate HUMMERs, and like the H3 Alpha, it offered a more powerful engine as well as unique styling and comfort features.

The H3 is the newest model to carry the Alpha flag, and represents HUMMER’s first Alpha model engineered in conjunction with GM Performance Division. 

Award-winning interior and safety enhancements
The H3 Alpha shares the same widely admired interior as all H3 models, including detail revisions and enhancements that have been implemented across the lineup. New child safety locks for the rear doors and easier-to-use power window switches were introduced during the ’07 model year and reflect customers’ input.

Details matter, and our customers told us these details were particularly important, so we updated the H3 lineup to address them,” said Walsh.

Also new for the H3 Alpha and the entire 2008 H3 lineup are standard head curtain side air bags; they were previously optional. Additional standard safety features now found on all H3 models include:

  • StabiliTrak electronic stability control system
  • Four-wheel antilock brakes with traction control
  • Dual front air bags with Passenger Sensing System
  • Tire pressure monitoring system
  • Vehicle-to-vehicle crash compatibility
  • LATCH rear child seat anchors

HUMMER’s Rear Vision system and a navigation system are available. The Rear Vision system uses a camera mounted near the rear bumper to provide a view of objects directly behind the vehicle. Also, the safety and security of OnStar is standard, and its new Turn-By-Turn Navigation feature is available.

Powertrain details
The H3 Alpha’s 5.3L engine is a powerful and efficient member of GM’s legendary small-block V-8 family. It is rated at 295 horsepower (224 kW)* and 317 lb.-ft. of torque (438 Nm)*; and is similar to the small-block V-8 found in the Chevy Silverado, which was named the 2007 Truck of the Year at the North American International Auto Show.

For jobs such as towing personal watercraft up a mountain to the lake, the small-block V-8’s torque performs with effortless ease and little impact on fuel mileage,” said Christopher Meagher, assistant chief engineer of small-block V-8 truck engines. “The 5.3L engine greatly broadens the H3’s towing capability.

Effortless highway driving also is an attribute of the 5.3L V-8, which enables 0-60 mph performance of approximately eight seconds.

All of the powertrain options in the H3 lineup deliver performance suited to different driving styles and needs,” said Meagher. “But when it comes to certain tasks such as towing, there is sometimes no substitute for a V-8 engine.

An aluminum cylinder block is used with the H3 Alpha’s engine. It helps reduce overall mass and maintains a more desirable front-to-rear weight balance. Like all of GM’s small-block V-8 engines, highlights include:

  • Deep-skirt cylinder block with cross-bolted main caps
  • High-flow cylinder heads
  • Electronic throttle control
  • 58X ignition system
  • E67 32-bit controller
  • Polymer-coated pistons with full-floating wrist pins
  • Returnless fuel system
  • Lightweight valvetrain
  • Steel camshaft
  • Low-restriction air intake system

GM’s small-block V-8 engines are engineered to meet today’s more stringent emissions standards. In fact, the H3 Alpha’s V-8 engine beats the deadline for new, U.S. federal emissions standards by a year. And compared to truck engines of a decade ago, the small-block engine family is approximately 90 percent cleaner. Cast iron exhaust manifolds matched with four close-coupled catalytic converters help reduce cold-start emissions, which is the largest source of vehicle emissions.

A Hydra-Matic 4L60 electronically controlled four-speed automatic transmission is paired with the H3 Alpha’s V-8 engine. And, as with all H3 models, flat-towing is enabled.     

New V-8 drives vehicle-wide enhancements
HUMMER H3 and GM Performance Division engineers did more than simply shoehorn a V-8 engine into the H3’s engine compartment. Accommodating the new power plant necessitated the execution of a seemingly endless number of technical details – many of which have been implemented across the entire H3 lineup.

The H3’s frame was modified to accept the V-8 engine, and a special oil pan was designed to ensure constant oil pressure when driving on steep grades – a hallmark of HUMMER’s off-road capability. Also, the engine compartment front of dash was modified to accommodate the V-8, and a new steering system is used on all H3 models to deliver better on-center feel and even more improved off-road reliability.

To support the torque output of the powerful V-8, the H3 Alpha’s front differential case is made of cast iron; other models feature an aluminum case. New engine mounts, higher torsion bar rates to support the increased mass, and specific shock valving also are unique to the V-8-powered model, ensuring it continues to deliver the unparalleled ride quality – both on- and off-road – that customers expect.

All of the chassis and suspension changes were validated in real-world testing on off-road trails in Moab, Utah, the Rubicon Trail and other challenging off-road venues.

Our engineers live, breathe and eat off-road driving,” said Walsh. “To say they sweat the details is an understatement.

A HUMMER by any measure
All H3 models pack HUMMER’s trademark capability into a midsize package. Compared to the H2, the H3 is 16.9 inches (429 mm) shorter in length, six inches (152 mm) shorter in height and 6.5 inches (165 mm) narrower. Roughly the same length as a midsize family sedan, H3 comfortably navigates city traffic and fits nicely in parking garages.

The H3 lineup also delivers exceptional rock crawling and climbing performance; it was engineered for off-road leadership among midsize SUVs. The heart of this capability is its electronically controlled four-wheel-drive system and suspension tuning tailored for off-road performance. In addition, the H3 features standard underbody shielding, brake traction control, and an optional 4.03:1 transfer case with rear locking differential.
Among its off-road credentials, the H3 can ford 24-inch (610 mm) streams at a 5-mph pace, climb 16-inch (407 mm) vertical steps and rocks, make its way through deep sand and race easily over sandy surfaces.

H3’s more maneuverable size provides advantages, such as a 37-foot turning circle that is about the same as a typical compact car, making easy work of parking lot maneuvers and tight turns when off-roading. The 9.1-inch (231 mm) ground clearance and maximum breakover angle of 25 degrees (with 33-inch tires) both make it possible to clear large obstacles in off-road driving. Serious off-road performance is also aided by the maximum approach angle of 39 degrees and maximum departure angle of 37 degrees. These approach and departure angles permit the H3 to drive into a hole and back out again, without getting hung up in the front or rear.

The H3 is sold in 34 countries, with production in the United States and South Africa.

*Pending SAE certification.





Body style / driveline:

4-door, 5-passenger hard-top 4-wheel-drive

EPA vehicle class:

midsize sport utility


welded steel frame, electro galvanized steel

Manufacturing location:

Shreveport, La.

Key competitors:

Toyota 4Runner; Jeep Grand Cherokee, Jeep Wrangler Rubicon Unlimited, Toyota FJ Cruiser, Nissan Pathfinder, BMW X3



5.3L V-8

Displacement (cu in / cc):

325 / 5328

Bore & stroke (in / mm):

3.78 x 3.62 / 96 x 92

Block material:

cast aluminum

Cylinder head material:

cast aluminum


OHV, 2 valves per cylinder

Ignition system:

coil near plug, composite intake manifold, platinum-tipped spark plugs, low-resistance spark plug wires

Fuel delivery:

sequential fuel injection

Compression ratio:


Horsepower (hp / kW @ rpm):

295 / 224 @ 5200*

Torque (lb.-ft. / Nm @ rpm):

317 / 438 @ 4000*

Recommended fuel:

regular unleaded

Maximum engine speed (rpm):


Emissions controls:

close-coupled catalytic converter, Quick Sync 58X ignition, returnless fuel rail, fast-response O² sensor

Fuel economy (mpg city / hwy):




Hydra-Matic 4L60


4-speed electronically controlled automatic

Gear ratios (:1):












Stall ratio:


Final drive axle ratio:


Low range lock gear reduction:

2.64 std, 4.03 opt

Crawl ratio (range):

33:1 std, 50:1 opt




independent SLA torsion bar, 46-mm monotube gas-charged shocks, 36-mm tubular stabilizer bar


“Hotchkiss” design multileaf, semi-elliptic dual-stage leaf spring, 46mm mono-tube gas-charged shocks, 25mm rear solid diameter stabilizer bar

Steering type:

power-assisted rack-and-pinion, with tri-bushing mount design

Steering ratio:


Steering wheel turns, lock-to-lock:


Turning circle, curb-to-curb (ft / m):

37 / 11.3



electro-hydraulic power 4-wheel disc, 4-wheel anti-lock, four-piston opposed (fixed) front caliper/single piston sliding rear caliper with Dynamic Rear Proportioning

Rotor diameter x thickness (in / mm):

front: 12.4 x 1.1 / 315 x 28
rear: 12.28 x 0.47 / 312 x 12

Total swept area (sq in / sq cm):

front: 69.4 / 448
rear: 51 / 328


Wheel size & type:

16-inch x 7.5-inch aluminum


std: P265/75R16 all terrain steel-belted Goodyear radials    opt: LT285/75R16 on-/off-road Bridgestone radials (with ZM6 Off-Road Adventure package)

Spare tire:

full-size spare



Wheelbase (in / mm):

111.9 / 2842

Overall length w/ spare and 33-inch tires (in / mm):

186.7 / 4742

Overall width (in / mm):

85.5 / 2170.6

Overall height (in / mm):

74.5 / 1893

Track (in / mm):



front: 65 / 1651


rear: 65.5 / 1664

Minimum ground clearance front (in / mm):

w/ 33-inch tires: 9.1 / 231
w/ 32-inch tires: 8.5 / 216

Step-in height (in / mm):



w/ 32-inch tires: 24 / 609.2
w/ 33-inch tires: 24.7 / 628


w/ 32-inch tires: 24.5 / 623.5
w/ 33-inch tires: 25.3 / 643.5



Approach angle (degrees):

w/ 32-inch tires: 37.5
w/ 33-inch tires: 39.4

Departure angle (degrees):

w/ 32-inch tires: 35.5
w/ 33-inch tires: 36.5

Breakover angle (degrees):

w/ 32-inch tires: 23.5
w/ 33-inch tires: 25

Grade capability (percent):


Side slope capability (percent):


Water fording capability (in / mm):

24/610 (at 5 mph)

Curb weight (lb / kg):

4854 / 2206


Seating capacity:


Headroom (in / mm):



w/ sunroof: 39.9 / 1013
w/o sunroof: 40.6 / 1032 


w/ sunroof: 37.9 / 963.5
w/o sunroof: 39.9 / 1013  

Legroom (in / mm):



41.9 / 1063


35 / 890

Shoulder room (in / mm):



54.4 / 1381.3


53.5 / 1358

Hip room (in / mm):



53.9 / 1370


49.5 / 1258



Cargo capacity (rear seat up) (cu ft / L):


   Rear seat up:

29.5 / 835.3

   Rear seat down:

55.7 / 1577

Cargo area length (at floor) (in / mm):


   Rear seat up:

32 / 810.5

   Rear seat down:

63.5 / 1614

Cargo area height (rear floor to headliner) (in / mm):

37 / 939

Cargo area width between wheelhouses (in / mm):

42.1 / 1070

GVWR, standard (lb / kg):

6001 / 2728

Payload, base (lb / kg):

1150 / 521.6 (est.)

Fuel tank (gal / L):

23 / 87

Engine oil (qt / L):

6 / 5.7

Maximum trailer weight (lb / kg):

6000 / 2721 (est.)

Maximum tongue weight (lb / kg):

up to 450 / 204 (est.)

*Pending SAE certification.

Note: Information shown is current at time of publication.





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