Along with the other new technologies debuted in the X-TRAIL car comes a sophisticated new 4X4 system. The ALL MODE 4X4 system has been developed by Nissan to allow secure and relaxed driving under virtually all conditions, with electronics ensuring optimum drive is instantaneously delivered to each wheel. This is the first electronic four-wheel drive system to be seen in a compact 4X4 and is based upon the same principles as the Skyline GT-R system.
Where some 'lifestyle' 4X4s offer automatic four-wheel drive, this is often via a dual pumped system, whereby the slipping of one pair of wheels pumps up the system to bring in the other pair. Naturally, there is a delay of several wheel rotations until this occurs, but Nissan's ALL MODE system anticipates loss of traction and the time delay is just a few degrees of a single wheel rotation at most.
Under normal road conditions the system is front-wheel drive, saving on energy losses and saving on fuel. But as soon as the electronics detect any slippage, drive is apportioned to both axles.
By pushing the buttons on the fascia, either 2WD, Lock or Auto 4X4 can be selected. In Auto mode the system will automatically apportion torque to each axle as surface conditions demand. A centre clutch in the rear final drive is electronically activated and controlled to ensure the correct percentage of drive to each axle.
If the Lock button is pressed then drive is delivered to each axle due to the locked centre clutch in the ratio of 57:43 (front to rear). This is for serious off-road work or for extreme conditions – such as when starting off on a snow-covered incline or driving through deep mud. The system brings peace of mind under difficult conditions, and will automatically default to Auto once speeds build and the problem recedes.
The ALL MODE system offers instant and increased security over much of the competition when starting on snow or ice, when driving on side slopes or under a whole range of what would normally be difficult conditions, such as you might encounter on slippery roads or maybe on an outing to rural areas.
Dynamic Safety and Security
X-TRAIL is fitted with a whole array of electronic systems making X-TRAIL first in class for both active and passive safety. The interaction between these integrated systems produces a complete safety package.
X-TRAIL has the shortest braking distances in its class due to the lightweight, integrity of the suspension, and disc brakes on all four wheels. The discs are controlled by the four-channel, five-sensor ABS system which is activated by Nissan Brake Assist for reduced pedal effort and combined with Electronic Brake Distribution – all standard fitment. X-TRAIL offers a complete active safety package which brings confident and safe control to every manoeuvre. Because the systems are so integrated, the result of the technology is an extremely light, compact and efficient system.
Extensive sound-dampening measures within the monocoque chassis are joined by a comprehensive computer-analysed structure for body reinforcement and impact safety. Crush zones absorb energy, and are joined by SRS airbags for both front occupants. Seatbelts have pretensioners and load limiters – all standard for driver and front passenger.
Chassis and Suspension
The X-TRAIL vehicle has a monocoque construction for low weight with extreme torsional rigidity. Not having a separate chassis means that the floor of the cargo area and other parts can be tucked up high, making this compact 4X4 even more effective off-road.
The rigid chassis has front and rear subframes mounted to it with insulating structures between the two to reduce noise, vibration and harshness. The MacPherson strut and coil suspension used on the front of the vehicle also has a subframe insulator for further reductions, with an independent rear suspension using parallel links.
This light, stiff suspension, using aluminium for the transverse link, is set up to move the rear wheel centre trajectory backwards on compression, rather than forward, minimising tyre impact and providing a compliant ride under all conditions – both on and off road. The long-stroke suspension offers a supple off-road ride yet the on-road ride has been benchmarked against premium brand passenger cars.
The high and commanding driving position gives both total confidence and a clear view in all directions, yet X-TRAIL also has top-of-the-class turning circle and manoeuvrability, ensuring there is no penalty in choosing this modern compact 4X4 over a passenger car - there are only benefits. With torsional body stiffness increased even over Nissan's own passenger car standards, it's clear that X-TRAIL is designed to offer total control on or off the road.
Engines
YD22 2.2-litre turbo-diesel
This new-generation 4X4 has the first application of Nissan's common rail technology. The engine is an in-line 16-valve DOHC direct-injection four cylinder, based on the unit used in the new Nissan Almera Tino but with significant changes for use in an ALL MODE 4X4.
The major development is the use of common rail technology working in conjunction with Nissan's proven M-Fire technology which has been further improved for X-TRAIL. Instead of the usual distributor-type fuel-injection pump, which is mechanically activated, common rail injection is electronically activated at considerably higher pressures. The pressurised rail feeds through electronically controlled injectors on each cylinder, allowing for more accurate metering, at considerably higher pressure which gives better atomisation in the cylinders.
Mechanically simple, this electronic system produces higher torque, lower emissions, lower noise vibration and harshness (NVH) and lower fuel consumption, particularly when employed in conjunction with the M-Fire technology.
M-Fire (Modulated Fire) is unique to Nissan, and is currently used in the Nissan Patrol GR. It is based around three technologies:
- Formation of a strong swirl in the cylinders using dual intake ports – a tangential and a helical port. Under light and medium loads the intake is routed through the helical port, promoting a strong swirl action, but under heavy load the swirl control valve in the tangential port opens, increasing the volume of air inflow, and reducing the amount of swirl. This allows for complete burn, with virtually no unburned soot.
- Application of heavy exhaust gas recirculation (EGR). Recirculating the exhaust gas through the air intake lowers both the temperature and the oxygen concentration of the mixture, with a reduction of NOx emissions.
- Optimisation of the fuel-injection timing. Modulated Fire allows for later pre-mixed combustion than is usual in a direct-injection diesel, with injection starting around TDC (top dead centre).
Taking all these technologies together produces a new engine with significant improvements to power, torque, fuel consumption, noise and emissions.
QR20 2.0-litre petrol & QR25 2.5-litre petrol
With passenger car levels of refinement and good levels of both power and torque, this new-generation petrol engine possesses all of the attributes necessary for quiet and smooth on road driving and strong off-road performance
These all-new units have twin camshafts and 16 valves, run via a silent chain and controlled by continuously variable valve timing control (CVTC). Interfacing with the other engine management systems, the CVTC ensures optimum power at all engine speeds. Engine response is strong and immediate but it is also smooth and quiet. There is strong pick-up from well below 2000rpm, while the output is further refined by the fly-by-wire throttle.
Strong measures have been taken to minimise any vibration being created in the new engine. The block has a ladder-frame construction which improves strength, and reduces weight and resonance. Low-friction materials, lightweight items like the valve springs and the silent-running chain combine to offer a refined response under all engine loads. Any vibration is then countered by the twin chain-driven balancer shafts. The compact balancer system is situated below the crankshaft to help ensure a low centre of gravity.
The refinements have not been at the expense of serious off-road ability. X-TRAIL is a further reminder that Nissan has over half a century of 4X4 experience, so this compact 4X4 is packed with practicalities. For example, the resin intake manifold is raised higher than on a passenger car, so that the 4X4 can safely traverse water or deep mud.
The intake manifold is matched by dimensionally optimised exhaust manifolds with integrated catalysts. The all aluminium engine, and the whole vehicle, have been designed to be as light as possible, helping to improve response but also improving fuel consumption and lowering emissions. Every aspect has been examined in detail, from the precise fuel swirl in the shallow-bowl pistons to the variable two-way cooling system, to offer the maximum performance with the minimum consumption of fuel and other raw materials, and the maximum reduction in emissions.
The QR petrol engine has one of the lowest levels of noise, vibration and harshness in its class.
Transmissions
The 2.2-litre turbo-diesel engine produces such high levels of torque that Nissan's engineers have been able to debut the innovation of a six-speed manual gearbox in conjunction with the YD22 engine. The unit is capable of pulling higher gears than normal, so the spread of a six-speed gearbox is possible, allowing a very high gear for highway cruising, with the resultant benefits of low engine speed, low wear, low noise and low fuel consumption.
This torquey and powerful unit will make a relaxed cruiser as well as being capable of powering the compact 4X4 through difficult off-road terrain, all at low engine speeds.
The 2.5-litre QR25 petrol engine will have the option of a five-speed manual gearbox or a four-speed automatic transmission. The slick-shifting five-speed manual gearbox works easily with the high-torque engine, offering a relaxed drive.
The high-efficiency E-Flow automatic unit features three speeds plus overdrive. This highly reliable and efficient unit improves fuel consumption over previous models and has a mechanical lock-up on overdrive to improve consumption on longer journeys.
Because the compact 4X4 produces high levels of torque, the electronic gearbox can be kept simple and gimmick-free. With the fly-by-wire throttle and electronic throttle chamber (ETC), which are sensitive to both throttle pedal depression speed and angle, there is no need for any complex series of modes – the engine works out whether the driver wants high or low response rates and at what engine speed that requires a change up or down the gearbox.
Exterior Design
The overall design of X-TRAIL is a balance between road and trail, communicating sophistication with strength. The straight lines of X-TRAIL's profile project a muscular yet refined and dynamic look. Nissan's trademark 4X4 grille is balanced by stylish light clusters which incorporate the indicators, employing clear-lens technology.
The front and rear bumpers are smoothly integrated with the synthetic, anti-dent, flared fenders to accentuate the modern 4X4 styling.
X-TRAIL has a commanding presence, 4X4 combining in one package elements of passenger car styling and the outdoor rugged look of the true 4X4.
Interior Design
Getting in and out of X-TRAIL is easy thanks to the wide openings and the sills built in to the bottoms of the doors. These sills also help keep dirt away from clothing and shoes after a foray off-road. Gaining access to the cargo area is equally simple, with the wide door hinging from the roofline, offering shelter from the elements when loading or unloading. With the door out of the way, the full cargo bay width can be easily accessed, for manoeuvring awkward loads.
Once inside, the youthful and modern interior is spacious and accommodating, offering flexibility for occupants, luggage and lifestyles. The light and fresh interior has the benefit of what Nissan's designers call a 'skyroof', the largest sunroof in its class. X-TRAIL is also fitted with heat and ultra-violet reducing glass. The special glass can significantly cut solar making the cabin a cooler and more comfortable place to be and reducing the load on the air conditioning and therefore the environment.
Dominating the front fascia are the novel dials, which are set in the middle, between driver and front passenger. They are easy to see and require less re-focusing from road to dials than the usual dash design. Their other main advantage is that the driver's seat can be moved to whichever setting is best without there being any risk of the dials being obscured by the steering wheel. The driver also has the benefit of the high command driving position, in keeping with the authentic 4X4 design.
The two large front seats with wrap-round support are balanced by three positions in the rear, with all positions offering luxurious levels of personal space for legroom and headroom. Each position is well catered for with cup holders and places for personal stowage. In the front fascia there is also a pair of cup holders which will keep drink cans either warm or cold through the air-conditioning, and there is a large removable centre console between the front seats, all part of the innovative and clever storage solutions.
There is a choice of two trim levels depending upon model. The high-quality interior also features some original materials, with a new type of textured synthetic used for door tops and control panel with brushed aluminium. In the rear, the complete cargo area – floor, backs of the seats and the sides – is covered in a new dimpled plastic resin material which helps hold luggage and which can be washed out if necessary. With the reclining rear seats able to fold flat and the rear seat cushion removable the entire rear area is capable of being totally cleared – giving total flexibility for many different load and passenger configurations. Even items like mountain bikes can comfortably be accommodated.
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