Bassman

I have a question regarding how the AWD system works in the Terri, maybe its a stupid one but lets say the Terri is bogged well, from my understanding when the car senses wheel slip it transfers the power to the wheels that do have grip or in the case of the DSC it will monitor steering angle and adjust power to each wheel it senses to be in an understeer or oversteer situation to correct the problem. What happens then when no wheels have traction, will it just decide to throw in the towel and spin one wheel or will it still keep trying to find a wheel with traction, eg rocking the car, to get out? Essentially what Im asking is when the going gets tough is it going to be a 2 wheel drive or as good as a 4 wheel drive, traction wise?

 

chevypower

even real 4 wheel drives need to option front and rear diff locks for to ensure all 4 wheels always drive, the Territory would be no exception, and not even as good as the real ones.... the Territory doesnt even have LSD on the back, so you can count on only driving one wheel on the back and one on the front when you need all 4 to drive most. You can tell me all about traction control and how good it is, but i have even seen how limited the Quadra-Trac II system in the Jeep Grand Cherokee is. The Territory is not a replacement for a true off-roader, i think it's more for people used to sedans and station wagons, who want to try out some basic dirt roads from time to time. But why theres no rear LSD on it, i can't work out. Diff lock would be better though, like on the RTV.

Ferris

Like most things, you need to know how to use it.
I have taken mine up steep slippery slopes, and just by holding constatn throttle, the system did the rest nicely. I could feel it working hard

HOWEVER

one day recently I was on flat wet grass. When I floored it from a standstill, I went NOWHERE, just 4 big rooster tails !!!
When I took off slowly, no probs
In this scenario, with no existing vehicle speed to measure, torque was fedd to all 4 wheels, the TCS saw all 4 wheels spin up at the same rate, thought the car was moving correctly, and did nothing.
did it again, this time keeping it going, and tried to do a bit of "circle work"!!. As soon as I started to turn, the lateral motion must have made one of the wheels bite a bit harder thn the others, the system sensed the rotation discrepancy, and clamped down instantly.

So, naturally, I turned the TCS off and did a bit more circle work for fun !!! ;-)

johnydep

Good question.

I'll tell what I know,and maybe someone who has experienced the situation you describe can tell the rest.

The Terri's AWD works with the traction control and ABS, when a wheel starts to spin the brake is automatically applied, this causes torque to be distributed to the other wheels. This scenario continues as all the wheels loose traction, but since the brake has been applied on one or more wheel the process starts all over again on the brake stopped wheel.

DSC works by applying the brakes to one wheel, depending on understeer or oversteer. http://www.mucda.mb.ca/Stability.htm

Here is an explanation that is a little; http://autoweb.drive.com.au/cms/A_55...wsarticle.html
How does it work?

"Stability control combines the advantages of Ford's Anti-Lock Braking system (ABS) and Traction Control System (TCS) and multiplies the benefits of both," said Presser.

"The best protection against accidents is to avoid them completely and stability control utilises the latest technology from Bosch to provide Territory with Australia's first locally engineered vehicle stability control system."

Presser said stability control was designed to maintain stability when the vehicle approaches its physical limits, through programmed intervention in the braking system and powertrain or a combination of both.

"It works in tandem with ABS - which prevents the wheels from locking when the brakes are applied - and TCS, which limits wheelspin during acceleration.

"Traction control ensures the vehicle remains controllable under heavy acceleration that typically occurs taking off on slippery roads, negotiating a hill or accelerating out of a corner.

"Traction control brakes the driven wheel, which shows a tendency to spin, and adapts the engine torque to obtain maximum traction."

Presser said sensors located at each wheel calculated the slip of each driven wheel and initiated traction control if slip levels are deemed excessive. Consequently, traction control intervenes on all four wheels on the AWD version of Territory.

The system also continually monitors driver input via a sensor on the Electronic Throttle Control.

"As soon as the Electronic Control Unit (ECU) detects a deviation from desired wheel speeds, the speed of the spinning wheel is automatically reduced by brake intervention, without any action on the part of the driver.

"Simultaneously, the ECU intervenes via an electronic throttle valve actuator to reduce excess engine torque."

Presser described stability control as the next generation in driving aids, employing Territory's braking system as a tool for 'controlling ' the vehicle.

"When stability control assumes operation it makes use of the existing braking system. The basic function of the brakes - to decelerate or stop the vehicle - is enhanced as stability control maintains Territory's stability and desired course."

Presser said stability control incorporated three vital elements in addition to the traction control system hardware - a steering wheel angle sensor, a lateral acceleration sensor and a rotational yaw rate sensor.

The steering wheel sensor constantly monitors steering wheel angle, or the driver's intended direction of travel.

The yaw and lateral acceleration sensors track Territory's rotation around its vertical axis and its lateral motion.

"Stability control is constantly working in the background, monitoring all its sensors 50 times a second, to check the driver's steering wheel position, throttle pedal position, whether the driver is braking or not, and where the vehicle is actually going.

"By comparing the actual measured yaw rate with a calculated optimal yaw rate, the system is able to intervene early enough to reduce the risk of unwanted skids and potential loss of control.

"Specific braking intervention is then directed at individual wheels - such as the inner rear to counter understeer, or the outer front during oversteer. Stability control also modulates engine outputs to reduce wheel spin and vehicle speed when necessary. "

Ford engineers have worked closely with the Bosch team to ensure stability control complements Territory's car-like ride and handling characteristics.

Testing has been conducted on the ice-covered lakes of Sweden, on the harsh, rough gravel roads of the Australian outback, and also performed a variety of real world driving tests in Germany, Belgium, Luxembourg and Spain.

Presser stressed stability control could not defy the laws of physics.

"Stability control significantly enhances the safety window in which the driver can operate the car, but it cannot perform miracles.

"It is an incredibly useful and practical driving aid that has enormous potential to reduce the possibility of a crash."

Presser said the software came into operation during situations that could occur in everyday driving, often without the driver noticing it had happened.

"For example, if the driver approaches a bend that tightens more sharply than expected, the driver will suddenly turn the wheel in the intended direction of turn, but may be carrying too much speed to safely negotiate the turn.

"Or, if a driver swerves rapidly to avoid colliding with an object or another vehicle on the road, the vehicle may not respond quickly enough to following the desired path, or may over-respond, resulting in oversteer.

"In both examples stability control will immediately notice the angle of steering wheel input and the direction of travel and brake the appropriate wheel to keep Territory stable and under control

Bassman

Just came back from trying some things. First up i approached a small washout on a 45 degree angle, as expected, due to lack of suspension travel, it didnt take much to get the diagonally opposed wheels nearly in the air, and from there it goes nowhere, but what the car does differs depending on what parts of the dsc you turn off. Leave it fully on and you can feel and hear the car trying to brake the two diagonal wheels, they still spin but not very quickly. Turn off the first stage and the grinding abs noise doesnt occur as much and it seemed to want to go a little further with some rocking of the car. Turn off everything and even slight throttle application sees the wheels spinning uncontrollably, like a 2wd with open wheeler diff, no hope in hell in this mode of even tackling a speed hump. But for just going up straight steep hills, leaving everything on as normal was the best, i noticed a little slip here and there but could feel the traction going to the different wheels with grip, quite good really and surprised me a bit. I dont think i will be in the fully bogged scenario any time soon so i suppose the first one to do it can tell us what happens!

RAPTOR

Momentum is your friend!

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