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Saab enters the fastest growing market segment in the United States, the mid-luxury SUV segment, with a distinctive model offering the elegant style and responsive handling that Saab is known for. The Saab 9-7X is designed to be a driver’s vehicle. To achieve its dynamic road manners and comfortable, well-controlled ride, the Saab 9-7X uses a uniquely tuned double A-arm front suspension with front coil springs and a five-link, electronically controlled rear air suspension. For improved traction under difficult road conditions an advanced all-wheel-drive (AWD) system, which requires no input from the driver to activate, is standard on all models.

The Saab 9-7X uses firm front and rear suspensions, providing a low ride height, a large front stabilizer bar and stiff upper control arm bushings in the rear, all designed to provide good body control for confident handling. The P255/55R18 all-season radials were specially devel-oped by Dunlop to deliver road-gripping capability.

Saab 9-7X has standard four-wheel ABS. All brakes have 12.8-inch ventilated rotors. The front brake system utilizes dual-piston aluminum calipers. The steering gear is tuned for on-center road feel and smooth operation. The front section of the frame is stiffened with braces to help improve steering responsive and precise. An 18.5:1 steering gear ratio, together with stiff steering rack mounts, is designed to provide enhanced steering responsiveness and preci-sion.

“The Saab 9-7X emphasizes the ‘sport’ aspect of its sport utility vehicle nomenclature,” says Peter Augustsson, Saab’s president and CEO. “Like the soon to-be-launched Saab 9-2X mod-els, it is very dynamic and is a vehicle that you want to drive.”

How to put more ‘sport’ into a sport utility vehicle
Suspension systems in mainstream SUVs tend to be under-damped and over-insulated from the road. Steering is often vague, requiring considerable correction at highway speeds. Body roll during sharp turns may be noticeable. Consequently, the driver is left somewhat removed from the driving experience.

In contrast, Saab puts the driver in control, providing a responsive vehicle that offers reward-ing performance coupled with a reassuring feeling of what’s happening between the vehicle and the road surface. The chassis components of the new Saab 9-7X are specifically designed and its steering and handling tuned to provide Saab-like, fun-to-drive performance characteris-tics and superb ride quality. Main elements of the unique formula for the Saab 9-7X’s chassis include:

Responsive steering/handling in tight turns and good on-center feel
Excellent tire grip

Well controlled body roll

Good crosswind stability

A firm, but comfortable ride, capable of absorbing the sharp bumps and ridges of rough roads.

Saab’s first SUV is equipped with a double A-arm front suspension with coil springs, a
5-link solid axle electronically controlled rear air suspension and a rack-and-pinion steering system. The rear air springs are continually monitored by two sensors that feed data to a frame-mounted compressor/electronic control unit, which inflates or deflates the air springs as necessary in order to maintain the designed trim height of the vehicle. This helps keep the headlights, including the optional high intensity discharge (HID) lamps, in a consistent posi-tion to light the road ahead.

All shock absorbers are valved to help provide firm body control for confident handling. The diameter of the front stabilizer bar is 36 mm to help with body roll control. A rear limited-slip differential is standard. It was specifically selected to help dampen yaw reactions during high-speed maneuvers.

The 18-inch wheels have 8-inch wide rims, enabling the tires to spread out further and put a bigger footprint on the ground. The P255/55R18 all-season radials were specially developed by Dunlop to provide road-gripping capability. The wheels accommodate four ventilated-disc brakes with large 12.8-inch (325 mm) front and rear rotors. An anti-lock braking system (ABS) is standard.

The steering system: stiff, fast and responsive
The Saab 9-7X is equipped with hydraulically assisted rack-and-pinion steering designed to help provide precise steering response and a tight turning radius. An 18.5:1 steering gear ra-tio, together with stiffer bushings improves steering responsiveness and precision. In parking maneuvers, the 9-7X only requires 3.5 turns from lock to lock. The steering gear is tuned for on-center road feel and the front section of the frame is stiffened with additional braces to help make the steering responsive and precise.

Chassis tuning includes a new valve profile with high response rates for the steering gear, firm mounting bushings, and low-friction components within the steering gear. The bushings used to mount the steering rack are designed to help minimize compliance in the steering system that might compromise on-center feel. The gear uses new, low-friction components such as bearings (in place of bushings) and low-friction seals to provide smooth operation. Braces at the front of the main frame add lateral stiffness and support. Stiffening the front part of the frame makes the steering more responsive and precise by reducing compliance in the frame so that it begins to generate lateral force more quickly.

“The Saab 9-7X is an excellent example of Saab’s expertise applied to achieve sporty, driver- focused performance,” says Kjell-Åke Eriksson, Saab Executive Director for Future Products. “Although it offers excellent versatility, it is still a delight to drive with minimal body roll and a firm but subtle and quiet ride.”

Dual-stage front airbags and rollover sensing system
On top of its well-mannered vehicle dynamics, the Saab 9-7X features a comprehensive stan-dard safety package, including:

Dual-stage frontal air bags

Passenger sensing system

Rollover sensing system

Head curtain side airbags;

Front seatbelt pretensioners with load limiters

Front seat occupants belt buckle-up reminder.

During a frontal impact, the standard dual stage frontal airbags allow the Sensing and Diag-nostic Module (SDM) to choose a high or low inflation level based on crash severity when the seats are positioned toward the rear of the seat track for taller occupants. However, when the seats are positioned toward and near the front of the seat track, as for small occupants seated closer to the airbag, a switch in the seat track informs the SDM and limits the airbag to a less aggressive inflation level.

A passenger sensing system (PSS) is used to automatically switch the right front air bag on or off, based on the passenger’s weight and the type of pressure on the seat. The PSS combines inputs from a pressure sensor on a bladder located in the seat and a belt tension switch to de-cide whether the airbag should be suppressed or enabled. An indicator in the rear view mirror signals whether the passenger airbag is "on" or "off". Even with this innovative feature, pas-sengers should always wear their safety belts and be sure that children are properly restrained in the rear seat.

Standard head curtain side air bags are designed to help provide head protection in certain side-impact collisions and rollovers for all outboard-seated occupants. The new rollover sens-ing system is intended to help protect occupants during rollovers by triggering the head cur-tain side air bags and activating the front seatbelt pretensioners.

The rollover-sensing module (ROS) is located on the center tunnel under the rear seat and uses a complex algorithm to deploy safety systems in rollover events. The ROS is designed to measure the lateral and vertical accelerations of the vehicle, as well as the roll rate. It obtains the vehicle speed from the wheel speed sensors. These four inputs are used to help make a predictive deployment decision. Once the ROS makes its deployment decision, a message is sent to the central control unit, or sensing diagnostic module (SDM), which is designed to then deploy the appropriate safety systems.

Seat belt load-limiting retractors with pretensioners are also standard for the front seat. Pre-tensioner front seat belts are designed to help minimize forward movement during a frontal collision and vertical movement in a rollover. A device attached to each front seat belt retrac-tor and triggered by the SDM at the same time as the air bags is designed to remove belt slack during a collision to help restrain front seat passengers. An energy-absorbing element built into the belt retractor helps regulate the forces on an occupant’s upper torso.

The Saab 9-7X features a front seat occupants safety-belt reminder, which lets front occu-pants automatically know via a chime and indicator light if their safety belt hasn’t been fas-tened.

The Saab 9-7X also provides knee bolsters that meet FMVSS 208’s new, more stringent stan-dard. The driver’s side bolster includes a metal panel with reinforced ribbing, which is located behind the plastic bolster surface, and in front of the energy-absorbing brackets. The panel more evenly distributes knee-loads into the energy-absorbing steel brackets, which are de-signed to crush during severe impact. The passenger-side glove box door is also engineered to act as a knee restraint and also meets the new FMVSS requirements.
 
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