|As the saying goes, it isn’t
bragging if you can back it up. The HUMMER H1 can do things that no
other vehicle in the world can do—like scale 22-inch rock ledges,
ford 30 inches of water and climb 60-percent grades. These uncompromised
and unrivaled off-roading capabilities allow the H1 legitimately to
stake its claim as the ultimate all-terrain vehicle.
the beginning, the H1 was designed above all to be capable. Built
to military specifications, the HUMVEE spin-off H1 is rugged to
the core,” said Michael C. DiGiovanni, HUMMER general manager.
“There isn’t another vehicle on the planet that performs
Power for any occasion
For 2004, the HUMMER H1 is powered by a 6.5L, turbo-diesel V-8 engine
that delivers 205 horsepower at 3400 rpm and an impressive 440 lb.-ft.
of torque at 1800 rpm. That’s 10 horsepower and 10 lb.-ft.
of torque more than 2003, and meets the new federal emissions standards
for 2004. The enormous torque is an important element in H1’s
ability to crawl out of mud holes, up steep inclines and over rocky
H1’s powerful diesel is mated to GM’s Hydra-Matic 4L80-E
electronically controlled four-speed automatic transmission. Over
time, this transmission monitors the customer’s driving technique
and adjusts for driving style. The New Venture Gear Model 242 transfer
case enables the driver to customize the drivetrain configurations
to match virtually any terrain. The transfer case adjusts manually
from high gear for highway, to high-lock for slippery surfaces,
to low-lock for driving off road with maximum power and torque.
No pavement? No problem!
Power is useless without control, and H1 is designed to allow the
driver to go almost anywhere with confidence. H1 has a four-wheel,
fully independent suspension system and variable-rate heavy-duty
coil springs. The front suspension incorporates a large stabilizer
bar to improve handling and reduce sway when cornering. In tandem
with the wheel and tire assembly, H1’s suspension provides
a comfortable ride even on the roughest terrain.
Four-wheel drive is standard on every H1 and features TorqTrac
4 technology. It automatically reduces tire spin on severe terrain
or slippery surfaces by applying the brake to the spinning wheel.
This allows the differential to redistribute torque to those wheels
As if that weren’t enough, H1 owners may opt for the Off-Road
Adventure Package. This package is the ultimate in off-road equipment
and includes front and rear Eaton ELocker locking differentials.
Activated instantaneously at the push of a button, the front and
rear differentials can be locked for optimum slow-speed capability
in climbing over large rocks or long, steep grades.
The Off-Road Adventure Package also includes a 12,000-pound winch
kit; 17-inch, 2-piece aluminum wheels with dual beadlocks; and Goodyear
Wrangler MT/R tires. Goodyear GSA tires can be substituted for the
Leaving the civilized world behind
Other SUVs claim the ability to take their owners off the beaten
path. Few, however, can truly leave the civilized world behind.
By the numbers, the H1 can traverse a 60-percent incline, a 60-percent
decline and a 40-percent side slope. It can clear a 16-inch straight
ground clearance obstacle and climb a 22-inch vertical step one
tire at a time. The truck can also ford 30 inches of water, which
is why there are drain plugs in the floorboards.
The following are just a few of the features inherent in every
H1 to ensure an off-road adventure second to none:
Dimensions and design
The H1 has the unique combination of a low center of gravity yet
a high, 16 inches of ground clearance—almost double that of
any other 4x4. A long wheelbase (130 inches) and nearly 72-inch
wide track give it the famous HUMMER stance of wheels at the far
corners of the truck. The placement of the wheels provides the key
to H1’s off-road prowess, an approach angle of 72 degrees
and a departure angle of 37.5 with a break-over angle of 35 degrees.
On the 17-inch aluminum wheels are 37-inch heavy-duty off-road tires.
The body is made of flexible, lightweight, corrosion-resistant aluminum.
The heat-treated aluminum body panels are bonded together with a
structural adhesive and riveted—just like an aircraft allowing
the body of the vehicle to flex in uneven terrain. This riveted
technique is expensive but the flexibility it provides is an important
element of the truck’s off-road performance.
H1’s four-channel ABS four-wheel power disc brakes are mounted
inboard as a component of the axle assembly, making them less vulnerable
to damage than conventional wheel-mounted components. By tucking
the brakes inboard, H1s can protect the brakes from mud, sand, silt
or water during off-road maneuvers.
Whether on or off road, safety and control are all about traction.
That’s why every H1 comes standard with one of the most useful
torque delivery systems in the world: the geared hub. In actuality
a mini gearbox right at the wheels, the geared hub takes incoming
axle speed and further steps it down at a ratio of 1.92:1, effectively
delivering twice the amount of torque to each wheel. Combined with
the rest of the drivetrain, the geared hub gives the H1 a total
gear reduction of 3.33:1.
Another signature feature of the H1 is the Central Tire Inflation
System (CTIS) with Runflat Tires. CTIS enables H1 owners to adjust
tire pressure on the move to adapt to varying terrain. H1 off-roaders
have the unique flexibility to drive on highway (32 psi) to a trail
and then deflate their tires (22 psi) for maximum off-road performance
without stopping the truck. Due to the hard rubber wheel inside
the H1 tire, H1’s Runflat Tire System enables drivers to continue
driving on a “flat” tire for up to 20 miles at 30 mph—ideal
when the nearest service station is not right around the corner.
Frame and rocker panel protection
A welded steel box frame that is bolstered by five heavy-duty cross
members, is strategically located on the H1 to absorb the stress
of operating in severe terrain at full Gross Vehicle Weight. Additional
driveline and rocker panel protection is featured on the truck to
protect the vehicle underneath. The 3/16-inch thick T6 aluminum
rocker panel and tubular protection help provide confidence that
boulder and body damage are less of a concern off road in an H1.
Don’t worry about packing light when taking the H1 off road.
In fact, a heavy load of up to 4,000 pounds won’t sacrifice
an ounce of the truck’s performance on or off road. Built
to military hauling specifications, the H1 can accomplish its most
extreme off-road tests fully loaded. The truck also is capable of
towing over 7,000 pounds.
Tight corners on the trail or the occasional street U-turn are surprisingly
simple with H1’s tight 26.5-foot turning radius.
A sealed central venting system protects major drivetrain components
from contamination. A 1/4-inch diameter hose connected to the vent
on each component leads to a central hose connected to the air filter.
This equalizes the pressure inside the gearboxes, enabling H1 to
operate in up to 30 inches of water, while minimizing the threat
of water, sand, silt or mud contamination.
Heavy-duty multiple cooling systems provide the H1 superior cooling
capability for engine coolant, engine oil, transmission/transfer
case fluid and power steering fluid. Maintaining fluids at the correct
operating temperature increases the life of the powertrain components
and allows H1 to operate under even the most extreme conditions.