NEW 2007 DEFENDER All new from the inside out

0
43

The Land Rover Defender can trace its heritage back to almost 60 years of ongoing development. But the list of improvements introduced in the New 2007 Defender represents the single most comprehensive re-engineering project of the stalwart vehicle to date.

These latest improvements reinforce Defender’s unassailable position as the ultimate all-terrain utility vehicle, while gaining significant ground in terms of on-road comfort and refinement.

Vitally, expanding the New Defender’s breadth of capability has gone hand in hand with reinforcing the vehicle’s reputation for strength and durability – a reputation underscored by the fact that more than two-thirds of Land Rovers ever built remain in use today.

Drivetrain

One of the most significant changes heralded by the launch of the New 2007 Defender is the debut of a state-of-the art, 2,4-litre four-cylinder turbodiesel engine. The compact, durable unit produces a maximum power output of 90 kW at an effortless 3 500 r/min.

While the power output remains unchanged compared with the outgoing Td5 engine, the new unit’s remarkably flat power curve makes more than 90 percent of peak power available across the useable rev range from just 2 200 r/min. The result is more accessible power than ever before.

At 360 Nm, torque output is up 20 percent over the outgoing Td5, with the torque peak achieved at a mere 2 000 r/min. More than 87 percent of that maximum (315 Nm, to be precise) is available from only 1 500 r/min to 2 700 r/min, ensuring that the new engine’s relaxed pulling power is more than a match for the toughest of tasks.

Exhaust emissions are substantially reduced too; actual emission levels vary by derivative and market (to cater for fuels with high sulphur content), but in every case, the New 2007 Defender’s emissions fall well within legislative demands, and comfortably exceed the demanding EU4 standard in Europe, as well as the EU2 standard on local soil.

CO2 emissions over the EU drive cycle are improved by 6 percent to 262 g/km on Defender 90 models, with a 3 percent improvement to 291 g/km on the larger 110 models. The cleaner emissions are linked to improved fuel efficiency, too.

Gary Taylor, New Defender’s chief programme engineer, says the new engine’s performance, emissions and durability are all hugely impressive. In particular though, seasoned Defender owners will really value the step change in refinement.

“The new engine is lighter and more efficient than its predecessor, yet stronger and more willing. It’s exactly what our customers asked for, because beyond its duties in the field, Defender also serves as the daily transport for a great many farming and rural families around the world.”

Among the key attributes ensuring the new engine’s strength and longevity are the deeply ribbed engine block, produced from cast iron to balance excellent stiffness with high levels of noise attenuation.

The engine’s immensely strong forged steel crankshaft features five main bearings and induction-hardened journals to help assure lifelong durability, while the sinter-forged con rods are produced from a high-strength copper-steel alloy. Every component has been designed with durability and longevity in mind.

The computer-optimised aluminium pistons balance weight  (for smoother engine running), with commercial durability standards. The strong, durable die-cast aluminium cylinder head is home to twin overhead camshafts operating 16 valves.

The camshafts are chain driven to help eliminate high-mileage servicing requirements, while hydraulic lash-adjusters on the valve rockers help minimise maintenance and reduce valve operating noise too.

A Honeywell-Garrett variable nozzle turbine (VNT) turbocharger is specified to help minimise turbo lag. Depending on the driver’s torque demand, the variable nozzle aims incoming exhaust gas onto different areas of the turbine wheel.

This allows the specification of a small and lightweight turbine wheel that can achieve very fast turbo responses at low engine speeds, and yet still deliver huge amounts of torque further up the rev range.

The technology provides more immediate and progressive accelerator responses than can be achieved with conventional, fixed geometry turbochargers. The variable nozzles can also close the turbo down at high engine speeds, eliminating the need for a potentially unreliable turbo wastegate.

Advanced combustion system

The new engine’s advanced conventional combustion system, dubbed Gemini, has been developed to ensure efficient combustion across the entire engine speed range. Key to this is the efficient mixing of atomised fuel across the gasses inside the cylinder.

The engine achieves flow efficiencies on a par with directly ported engines and swirl ratios similar to engines with twin-helical ports. This helps deliver the unit’s remarkable balance of fuel economy and low emissions.

To help reduce combustion noise, the engine has been designed to operate at a compression ratio of only 17.5:1. This also helps reduce in-cylinder combustion temperatures for lower emissions. Further reductions in part-load emissions are achieved by an advanced water-cooled exhaust gas recirculation system.

The engine’s third generation common-rail fuel-injection system has a high-pressure pump that can operate at pressures of up to 1800 Bar.

In fact, the Gemini system is so effective that the engine has been tuned to operate with peak fuel pressures of only 1600 Bar, helping to further improve reliability in ultra-high mileage applications.

The high-speed solenoid fuel injectors approach the performance of injectors with piezo-electric actuators, but without the added cost and complexity. They achieve up to five discrete injection events during a single combustion cycle, allowing a remarkable balance of performance, economy and refinement.

Robust intake, exhaust and cooling systems 

The New 2007 Defender retains the hallmark air-intake grille on the right hand fender, well clear of the vehicle’s 500 mm wading line to prevent the engine from sucking in water.

A new filter housing employs vanes with an ingenious cyclone feature designed to help separate out dust particles before they clog up the filter. This helps prolong the filter’s service life in dusty environments.

The new exhaust system is produced from heavy-gauge stainless steel and features a 2,0-litre close-coupled ceramic catalyst brick.

The high capacity cooling system employs a pressure relief thermostat that controls coolant flow into the engine based on engine outlet temperature. This permits the use of an unusually low spring rate for the thermostat in the interests of high-mileage durability.

An 11-blade fan ensures sufficient cooling airflow to the engine during prolonged high-power, low-speed operations in even the hottest of climates. Thermostatically controlled by a robust viscous coupling, the fan only operates when necessary, helping to minimise fuel consumption.

Improved transmission and four-wheel drive system

The New Defender’s transmission retains the highly capable, dual-range, permanent four-wheel drive configuration of its predecessor. However, all the major components have been upgraded or replaced to match the new engine’s improved performance.

The new driveline includes a new six-speed, manual gearbox, as well as detailed improvements to propshaft layout and driveline joint specification, all in the interests of off-road performance, improved refinement and enhanced durability.

The changes provide better control when towing or driving off road, reduce cruising noise, lighten clutch loads and improve gear change precision. They not only provide the New 2007 Defender with an even wider breadth of capability, but everyday use easier.

Wider gear ratio spread

The New 2007 Defender’s MT82 six-speed gearbox features a wide ratio spread to facilitate low gearing for improved control off-road and high gearing to achieve good on-road fuel economy and refinement.

First gear is a substantial 32 percent lower than the outgoing unit, while the new sixth speed is 34 percent higher than top gear in the previous R380 gearbox.

The new gearbox’s ratio spread has enabled Land Rover to further optimise transfer box’s high and low range capability. In normal driving, this extends the gradeability and towing capabilities of the new vehicle.

It allows less frequent engagement of low range in day to day use, while the increased high range gearing of the new transfer box provides a deliberately tall cruising ratio that makes the most of the new engine’s broader torque spread to deliver more relaxed cruising and improved real-world fuel economy.

The overall effect of these changes is a dramatic increase in gear ratio spread that equips the New 2007 Defender with an unprecedented combination of open road refinement, working ability and terrain capability.

New six-speed gearbox

The new MT82 gearbox is an acclaimed six-speed in-line transmission produced at Getrag-Ford Transmission’s award winning facility at Halewood in the UK.

The unit is designed exclusively for commercial applications and has proved robust, strong and durable across a wide range of applications. Unusually, the two-shaft design features a forged aluminium centre plate that supports an intermediate third bearing for the output and countershafts. This is designed to prevent damaging rotational bending that could otherwise be initiated by the new engine’s very high torque output.

A generous synchromesh specification helps to ensure excellent gear change quality. Triple synchromesh cones are specified on first and second gears, double cones on third and fourth and single cones on fifth, sixth and reverse.

An internal breather system provides the gearbox with robust protection against water ingress during extreme wading, while a unique die-cast aluminium rear casing has been specified to permit the ergonomic repositioning of the gearshift lever within the Defender’s new cabin.

The new engine makes the most of the driveline’s improved gearing thanks to individual accelerator pedal ‘maps’ for different gears. These help ensure throttle progression and control are better than ever before. In addition, improved, stronger anti-stall characteristics help to widen the vehicle’s terrain-crawl envelope.

Permanent four-wheel drive

Like the outgoing model, the New 2007 Defender features permanent four-wheel drive. Power is directed to front and rear axles by a centre differential, located within a central two-speed transfer box.

Like the current Defender, the transfer box features a driver-selectable differential lock to help provide reliable power transmission in the most arduous conditions. It retains the ‘H’ gate selector that allows the driver to control both transfer box gear range and differential lock with a single lever.

The New 2007 Defender’s transfer box has been comprehensively improved, including the use of finish-ground gears, while new, more robust selector mechanisms are designed to improve gear shift precision and reduce shift effort.

Driveline and clutch

Even the New 2007 Defender’s propshafts have been improved. The refined propshaft geometry is designed to help further extend the life of the system’s constant velocity joints. The joints themselves have also been upgraded.

Defender’s new large-diameter clutch not only provides welcome reductions in operating load, but also offers improved feel for better launch control and driveability in both on and off-road applications.

The unusually large pressure plate copes admirably with clutch abuse by providing the clutch with a high thermal capacity, while the clutch linings have been specially selected for their excellent high-temperature recovery characteristics.

Chassis improvements

Wide ranging steering and suspension changes ensure the New 2007 Defender is easier and more rewarding to drive.

New springs and redesigned dampers, together with revised castor geometry, broader anti-roll bar specification and retuned power steering, have enhanced dynamic response across the entire range.

The New 2007  Defender feels more agile and composed, regardless of load or terrain. The new dampers feature upgraded valves and for better responses and improved consistency. These combine to improve body control and ride comfort.

The New Defender retains its predecessor’s reputation for class-leading axle articulation and suspension travel, essential for successful negotiation of the most challenging off-road terrain.

Suspension hardware is drawn from the outgoing vehicle, with front axle location courtesy of forged steel radius arms and a Panhard rod, while the rear axle is suspended by trailing links and a centrally mounted A-frame.

The hydraulically assisted, variable-ratio steering box responds 34 percent faster on full lock than straight ahead. This balances relaxed, open-road steering with sharper responses at high lock angles for better control over difficult ground. A large steering damper helps control steering kickback over challenging terrain.

Immensely strong chassis

The New 2007 Defender is built on a modified version of the previous model’s famously strong ladder-frame chassis.

The deep, closed-section frame offers inherently superior stiffness to the open-section designs used by some competitors, while computer-controlled welding helps ensure accurate control of both frame geometry and joint quality.

To protect the frame against years of harsh use, it is subjected to a multi-stage dip-tank electrophoretic painting process to provide very high standards of corrosion protection for assured longevity.

As with all Land Rovers, the chassis frame has been designed to withstand the very high loads experienced during snatch-recovery. Seasoned off-road users will also appreciate the readily accessible jacking tubes, conveniently located at the end of each longitudinal chassis leg.

Braking system

The New 2007 Defender’s all-round disc brakes are as impressive as ever. The front brakes feature four-piston opposed action callipers, while twin-piston opposed callipers are specified at the rear.

The brake system has been deliberately configured to provide firm, short-travel pedal characteristics. This helps to ensure that predictable modulation can be achieved on even the most uneven terrain.

Defender is available with a high-resolution ABS system. The system’s front wheel speed sensors are located within the vehicle’s sealed hubs to protect from dirt ingress or stone and scrub damage, while special shields protect the rear units.

The sensors feature an unusually high 60-tooth pattern to help provide very accurate resolution of individual wheel speeds for excellent low-speed ABS control. The ABS system features industry-leading loop times (the time it takes the system to monitor wheel speeds, then calculate and execute the required hydraulic response), helping to optimise braking to match the challenging demands of the most varied terrain.

Traction control

The ABS modulator also controls the vehicle’s electronic traction control. By only using the brakes to control the speed of a spinning wheel, the system ensures there is no reduction in the torque supplied to other driven wheels. This is designed to help avoid the risk that Defender could become bogged down during periods of prolonged wheelspin, for example during uphill, off-road towing.

The New 2007 Defender retains the highly effective propshaft-acting handbrake. By operating on the propshaft, the brake’s already impressive holding torque is further increased thanks to the multiplication effect of the axle differential to provide excellent hill-hold capabilities in normal use.

If the centre differential lock is also engaged, the handbrake provides full four-wheel park braking for class-leading hill hold capability under the toughest of conditions.

Aluminium-intensive construction

The New 2007 Defender’s rugged bodyshell continues to employ a high proportion of lightweight, high strength aluminium alloys to help minimise weight and reduce the vehicle’s centre of gravity.

Aluminium provides other benefits too. Manufacturing large, vulnerable panels like the rear load floor and body sides from alloy helps protect against corrosion in areas of the vehicle that will inevitably suffer paint damage over the Defender’s long working life.

Double-sided zinc coated bake-hardening steels are used in critical areas of the body where formability and dent-resistance render aluminium unsuitable (including the new bonnet, which is engineered to be more durable than even the old heavy-duty bonnet assembly).

Manufacturing

The New Defender’s body assembly process has been subjected to a comprehensive quality improvement programme, designed to ensure that build quality of the New 2007 Defender is better than ever before.

The resulting improvements in the dimensional accuracy of key body surfaces also helps improve the effectiveness of Defender’s weather and noise sealing systems.

The New 2007 Defender benefits from the same rigorous pre-treatment and painting processes as Land Rover’s most prestigious Range Rovers. In total, the body is subjected to over 50 discrete processes, assuring the highest standards of cosmetic and functional paint performance.

Naturally, water-based paints are used to minimise emissions of volatile organic compounds during manufacture.