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SPECIAL

Ford Territory

SPECIAL

Ford Territory

Stronger, Quieter Engines

Staff, Wednesday October 31, 2001.

Page 1 of 1

The new engines are matched to improved manual and automatic transmissions, sophisticated new electronic engine controls and a refined Control Trac? four-wheel-drive system.

Lightweight V8

Explorer's 4.6 litre Single Overhead Cam (SOHC) V8 engine - the first all-aluminium entry in a Ford off-roader - delivers 178kW at 5100 rpm and 382Nm of torque at 3700rpm.

The engine delivers healthy torque at low revs, allowing for responsive around-town driving and freeway cruising.

The engine's reliable coil-on-plug design eliminates conventional spark plug wires.

4.0-litre V-6

The proven aluminium-head, 4.0 litre, SOHC V-6 engine offers 157kW at 5100 rpm and 344 Nm of torque at 4000 rpm.

The torque curve for the 4.0 litre engine is designed to be relatively level across the entire rev range, providing strong performance at nearly any engine speed.

An all-new, equal-length composite plastic intake system was added for improved sound-damping, while engine durability was improved through the use of aluminium main bearings.

Both engines meet US Low Emissions Vehicle (LEV) standards. Fuel economy has been held constant - even with a larger vehicle and one that can seat two more passengers than the prior model - thanks to several weight-saving innovations.

An all-aluminium hood and V-8 engine block, along with a magnesium cross bar beam saves approximately 40 kilos.

New automatic and manual transmissions

For the first time, the XLT Explorer is available with both manual and automatic transmissions. Both offer improved operation and greater efficiency than the units they replace.

The new wide-ratio, 5-speed, 5R55W5 automatic provides improved performance over most four- and five-speed transmissions. It is internally balanced for better NVH.

The transmission team's goals were to improve launch acceleration and quietness. A major step in that direction comes from Explorer's new 20kg single aluminium transmission casting. The single casting greatly reduces NVH and powertrain bending at higher speeds.

The transmission carries more torque through its new wide-ratio five-speed. First gear now has a ratio of 3.26 compared with 2.47 for the previous transmission.

Similar gains were made through the other four gears, giving the Explorer improved city and highway merging performance.

To reduce noise, Ford developed a quieter oil pump and new planetary gear designs. Planetary gears provide different ratios as a transmission goes through shifts.

A 4.30 axle ratio is standard on the manual XLT, while a 3.73 axle ratio and limited slip differential are standard with the automatic models.

The Explorer comes with a standard towbar and gooseneck receiver hitch, which has a towing limit of up to 1600kg. A heavy-duty Class II load levelling kit increases towing capacity to 2500kg.

New electronic engine controls

A next-generation 32-bit Powertrain Electronic Controller (PTEC) manages all engine and transmission functions, along with speed control and many other powertrain functions.

?The difference between this module and the previous one is like upgrading from a 286 computer to a Pentium,? Ford?s SUV and Light Commercial Marketing Manager, Kevin Lillie, said.

The new PTEC module integrates several electronics boxes for better reliability.

The electronic controller is so sophisticated that it raised national security issues during development. Because it uses a high-tech internal code, the United States Government at one point forbad engineers from taking it across international borders.

The main benefit of PTEC is that it allowed engineers to more precisely control engine functions - including combustion - under a broader variety of operating conditions. The result is better emissions control, reliability and efficiency.

Ford expects to use the PTEC in a broad range of vehicles in the future.

The PTEC allowed engineers to give the 4.6-litre V8 a fail-safe cooling strategy to prevent engine damage through overheating. When the cylinder head temperature rises too high as a result of coolant loss, the engine's electronic controls shut off fuel to alternating banks of cylinders - but continue to pump cool air through those cylinders - to allow the driver to drive a short distance without engine damage.

Explorer's transmission also benefits from this ?smart? electronics approach. Adaptive pressure control technology helps keep transmission shifts consistent over time, even as the transmission wears.

The same adaptive technology extends to engine controls. The powertrain control module adjusts for hundreds of variables, including throttle position - a key indicator of how the driver wants the engine to perform.

Control Trac?

Explorer's Control Trac? four-wheel-drive system has been refined to make it more ?transparent? to the driver, while improving its abilities in limited traction situations.

For the first time, the four-wheel drive system has its own electronic controller, which can be likened to the latest high-speed personal computer.

The extra computing power gave Explorer's engineers the ability to fine-tune the system to a wide variety of demands.

For example, sensors measure and compare front and rear drive shaft speeds, as well as throttle position. This allows the system to incorporate the driver's intent into the mathematical formula that determines how much torque to send to each axle.

These measurements are taken 50 times per second, for an almost seamless adjustment of the clutch that controls the transfer case output in the 4x4 system's ?automatic? setting.

If the rear wheels lose traction, the optimal amount of torque for the situation is transferred to the front.

But the system doesn't have to wait to sense slip before it takes action. For example, if the Explorer is sitting at rest in a four-wheel-drive setting and the driver presses the accelerator, the controller sends torque to both the front and back wheels within milliseconds and then samples the results. This heads off wheel spin in low-traction situations.

The Control Trac? system includes a pushbutton switch - versus the former rotary knob - on the instrument panel that allows the operator to select ?4x4 Auto?" ?4x4 High? or ?4x4 Low? modes.

In 4x4 Auto - recommended for most driving situations - the system continuously monitors conditions and adjusts front-wheel torque, combining transparent all-surface operation with highly capable four-wheel drive.

When in automatic mode, the Control Trac? drivetrain normally delivers all engine torque to the rear wheels. It uses an electronically controlled electromagnetic clutch to redirect up to 100 per cent of engine torque to the front wheels when it detects rear-wheel slippage or heavy throttle application.

In 4x4 High - recommended for severe winter weather and off-road conditions - the system effectively locks the front and rear driveshafts together to provide optimal traction of four wheels.

In 4x4 Low - recommended for low-speed off-road driving or high-torque situations, such as towing a boat out of the water - the system locks the front and rear driveshafts together but adds a 2.48:1 gear reduction, which provides extra pulling power.

Neither 4x4 high nor 4x4 Low is recommended for dry road operation.

An important consideration in designing the 4x4 system was to make sure the wheels don't ?bind? during turns in the automatic mode, providing uncomfortable feedback to the driver.

Built into the Control Trac? system is a smart control. Unlike typical mechanical 4x4 systems, Explorer's Control Trac? can even adjust for such variables as differences in tyre pressure.

By continually tailoring torque transfer before any slip is detected, the system actually helps prevent wheels from losing traction in the first place. The 4x4 system kicks in when needed without telltale pulses or harshness. The Control Trac? transfer case housing is made of magnesium for reduced weight.

ControlSlip rear driveshaft

The Explorer is also equipped with a patented new ControlSlip rear driveshaft, which provides exceptional stiffness for quiet performance.

It has safety benefits as well. In the event of a frontal impact, the driveshaft is designed to telescope, not buckle. This movement helps the vehicle further absorb impact forces and manage energy.

POWERTRAIN CHANGES AT A GLANCE

• New all-aluminium 4.6 litre SOHC V8 delivers 178kW and provides impressive low-end and mid-range torque.

• New maintenance-free, wide-ratio 5-speed automatic transmission gives customers improved city and highway merging performance and better NVH (CHECK).

• Refined 5-speed manual transmission (for the V6) delivers car-like shift quality in a robust powertrain.

• New high-tech electronic engine controls integrate several electronic boxes for better reliability.

• Improved 157 kW 4.0 litre SOHC V6 is now standard and features an all-new composite plastic intake system for improved sound quality and better durability.

• Improved Control Trac? four-wheel-drive system.

For further information, please contact
Ford Australia Communications
Phone: 03-9359 8491

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