Press Release
Chassis, Ride and Handling
While functionality and off-road performance are key features of the HUMMER H3, it also provides a surprisingly smooth, comfortable ride, along with responsive handling and braking control for daily driving. Key chassis features contribute to this combination of smoothness and control, both on- and off-road.
These include a fully welded ladder-type frame, with a modular, three-piece design that incorporates fully boxed components for outstanding strength and stiffness. It is combined with an independent front short/long arm (SLA) torsion bar suspension and “Hotchkiss” design multi-leaf, semi-elliptic, dual stage leaf spring rear suspension. They provide both excellent on-highway comfort and outstanding off-road capability.
A highly sophisticated standard power rack-and-pinion steering system, with a three-bushing design and a 17:1 ratio, contributes to a manoeuvrable 11.3-m kerb-to-kerb turning circle, about the same as a compact sedan. Meanwhile, electro-hydraulic four-wheel anti-lock disc brakes with Dynamic Rear Proportioning, give quick, controlled stopping power.
Stability and performance are further enhanced by a standard-fit single-wheel, full-function traction control system. This uses a combination of engine intervention and brake management to provide impressive traction capability with as many as three wheels on a slippery surface.
GM’s sophisticated StabiliTrak electronic stability control system is standard on the HUMMER H3. Partnered with the new brake and traction control systems, it provides more precise, controlled ABS stops, as well as enhanced traction/yaw stability.
StabiliTrak uses brake control to precisely manage the speed of each wheel as well as torque across the front and rear axles. Individual brake sensors at each wheel provide signals to the control module, enabling it to aggressively adjust brake pressure. The vehicle brake system provides torque-biasing to enhance traction and engine management as required to assist in controlling traction and yaw stability. The transfer case’s control algorithm has been integrated with the StabiliTrak and ABS systems to provide enhanced vehicle stability by managing the front-to-rear torque distribution.
StabiliTrak is always on and fully functional. It is automatically enabled, providing full stability, traction and ABS control, whenever the vehicle operates in forward gears. The system intervenes when it senses one or more of the wheels slipping or when the vehicle is not following the driver’s intended path. It detects slippage during braking or acceleration and automatically adjusts individual wheel brake pressure, engine torque and adjusts front to rear drive torque distribution, as required, to achieve optimal control.
The HUMMER H3 body and chassis structure also incorporates enhancements designed to help in crash protection, as well as a number of advanced safety systems to assist in both crash avoidance and protection. This includes a reinforced passenger compartment safety cage that helps provide protection in the event of side and frontal impacts.
The strong, rigid steel structure surrounds the passenger compartment, runs from the A-pillars to the roof rail, back to the D-pillars and includes the bottom rocker panels, underfloor longitudinals and frame. The all-steel body panels and exceptionally strong frame further help protect occupants in a collision. The fully welded, ladder-type frame optimizes crash performance, in addition to standing up to the rigorous off-road requirements.
To protect the chassis under the most arduous of off-road conditions, underbody protection incorporates four standard protective shields. These include a front skid plate; an oil pan skid plate that also protects the front axle; a transfer case shield and a fuel tank shield.
