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2003 HUMMER H1

As General Motors continues to grow the HUMMER brand, the foundation upon which that growth is built, the HUMMER H1, remains rock-solid. The original HUMMER, H1 is a one-of-a-kind vehicle, the world's premier off-road vehicle, rugged enough for Baja, refined enough for the country club.

"The H1 is what started it all," said Michael C. DiGiovanni, HUMMER general manager. "It's the vehicle that drew the interest of adventurous consumers across the nation, as well as the interest of GM. It offers superior off-road capabilities and terrific highway performance as well."

New rear differential locker for 2003
HUMMER H1 has some content and feature upgrades for the 2003 model year, most notably the availability of a rear ELocker locking differential from Eaton, which also appears on H1's new stable mate, the H2.

The rear differential lock operates at the push of a button. Activated instantaneously, it locks the rear differential for optimum slow-speed capability in climbing over large rocks or up long, steep grades. The two rear axle shafts rotate together at the same speed (this mode can only be accessed when the transfer case is in Low Lock, locking the center differential).

The dash-mounted switch to activate the system allows an electrical signal to go by wire through the differential housing and into the locker. In normal circumstances, the locker is "open" and is invisible to the driver. The rear end has full differentiation between the left and right wheels. Upon detecting the signal, the locker connects the right and left axle shafts and is fully "locked," providing superior low-speed off-road performance. The rear axles do not differentiate at all. They act as if they were one single shaft because they are electronically locked together.

Other new features
The 2003 H1 sports some new interior upgrades, including a new, larger radio face with cassette and single CD slot and an in-dash 12-disc CD changer.

The exterior of H1 features a new heavy-duty brush guard replacing last year's lighter standard one. Also, the exterior badge that formerly read "TT4/ABS" now reads "Torque Track 4" or "Torque Track 4 - ELocker," if the model is equipped with the optional ELocker described above.

For the 2003 model year, H1 adds two colors to its palette of seven: Summit Silver and Black Diamond Metallic. Those complement the existing colors of Competition Yellow, Black, Bright White, Ocean Blue Metallic, Metallic Pewter, Firehouse Red and Woodland Green.

Two models offered
HUMMER H1 models come in two model offerings: 4-Door Wagon and 4-Door Open Top.

As in years past, H1 is world-renowned for its intimidating presence. It has an impressive width of 86.5 inches and an overall length of 184.5 inches. The truck's low center of gravity, long wheelbase (130 inches) and 72-inch track make it extremely stable in varied road conditions and surfaces. Its 16-inch vertical ground clearance is almost double that of any other 4x4. Approach and departure angles of 72 degrees and 37.5 degrees respectively, enable ascent and descent of steep grades without vertical interference.

The H1 is powered by a 6.5L, 195-horsepower General Engine Products turbodiesel engine, which generates 430 lb-ft of torque. Its near-midship location provides excellent weight distribution. GM's 4L80-E electronically controlled four-speed automatic transmission allows smooth transition of power for improved mobility off-road. Over time, it 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.

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. The truck'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. H1's Central Tire Inflation System (CTIS) enables the customer to adjust tire pressure on the move and adapt to varying terrain. When the H1's tires are deflated, the size of the tire footprint is increased, providing better traction in snow, loose sand and mud.

SPECIFICATIONS

Overview

Model: HUMMER H1
Body style / driveline: four-door open-top, four-door wagon, four-wheel drive
Manufacturing location: Mishawaka, Indiana
 
Engine
Type: 6.5L Turbo Diesel V8
Displacement (cu in / cc): 396.7 / 6500
Bore & stroke (in / mm): 4.06 x 3.82 / 103.12 x 97.03
Block material: cast iron
Cylinder head material: cast iron
Valvetrain: OHV with rocker arms, pushrods and roller tipped lifters
Ignition system: compression ignition
Fuel delivery: indirect injection (IDI)
Compression ratio: 20.2:1
Horsepower (hp / kw @ rpm): 195 / 145 @ 3400
Torque (lb-ft / Nm @ rpm): 430 / 583 @ 1800
Recommended fuel: no. 2 diesel
Maximum engine speed (rpm): 3400
 
Transmission
Type: Hydra-Matic 4L80-E, 4-speed electronically controlled automatic
Gear ratios (:1):

First:

2.48

Second:

1.48

Third:

1.00

Fourth:

0.75

Reverse:

2.08
Final drive ratio: 4.92:1
 
Chassis/Suspension
Front: independent double A-frame, front stabilizer bar diameter 27mm
Rear: independent double A-frame
Traction control: brake intervention
Steering type: power-assisted
Steering ratio: variable 13/16:1
Steering wheel turns, lock-to-lock: 2.5
Turning circle, curb-to-curb (ft / m): 25.5 / 7.6
 
Brakes
Type: Hydra-boost, ABS, power disc brakes
Rotor diameter x thickness
(in / mm):
front: 10.5 x 0.94 / 266 x 24
rear: 10.5 x 0.94 / 266 x 24
 
Wheels/Tires
Wheel size and type: standard: 17-inch one-piece aluminum wheel with run-flatoptional: 17-inch two-piece forged aluminum optional
Tires: Radial, Goodyear GSA, 37x12.50R17LT or Goodyear MT/R, 37x12.50R17LT
 
Dimensions
Exterior
Wheelbase (in / mm): 130 / 3302
Overall length (in / mm): without winch: 184.5 / 4686; with winch: 190.5 / 4839
Overall width (in / mm): without mirrors: 86.5 / 2197; with mirrors: 101 / 2565
Overall height (in / mm): wagon model: 75 / 1905; open-top model: 77 / 1456
Track (in / mm): front: 71.62 / 1819; rear: 71.62 / 1819
Minimum ground clearance (in / mm): 16 / 406.4
Curb weight (lbs / kg): 4-door open top: 6814 / 3093; 4-door wagon: 7154 / 3247
Payload 10,300 GVWR (lbs / kg): 4-door open top: 3486 / 1583; 4-door wagon: 3146 / 1428

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