Jaguar goes four-paw

JAGUAR has announced it will introduce an all-wheel-drive system to its XF and XJ sedans as part of a 2013 model year update.

The all-paw system – developed in conjunction with sister company Land Rover – will be matched exclusively to Jaguar’s new 250kW/450Nm supercharged 3.0-litre V6 engine with idle-stop and ZF eight-speed automatic transmission.

The British-based company says it has developed the system in response to strong customer demand from markets with cold climates, such as the US and Russia, so an Australian launch is off the cards at this stage.

Jaguar Australia marketing and public affairs specialist Narine Salmasi told GoAuto that the system will initially be limited to left-hand-drive markets.

Jaguar claims to have conducted 18 months of ‘extensive’ cold weather and all-surface testing at the company testing facility in Sweden’s far north to make sure steering and suspension feel is as close as possible to the rear-drive versions.

The ‘intelligent’ all-wheel-drive system operates with a rear bias under normal conditions, but at take-off torque is pre-loaded to the front for a smoother start.

The electronic system constantly monitors grip levels, steering and throttle inputs, and will intervene “almost instantaneously” if wheel slip is detected by shifting up to 50 per cent of engine torque to the front wheels.

The cars will also feature a ‘Winter Mode’ for use on snow-covered or icy surfaces, further sharpening the system’s response times by pre-empting wheelspin.

Integration with the stability control and ABS braking systems also allows torque to be apportioned from side-to-side across each axle.

Jaguar Cars vehicle line director Ian Hoban said it was important for the system to retain the dynamic qualities of the rear-drive versions.

“What we are most proud of is the fact that our All-Wheel Drive system preserves all the dynamic qualities of our rear-wheel-drive Jaguar saloons in terms of handling, steering quality and ride refinement while adding a new depth of ability in low-grip conditions,” he said.

“The system delivers all the traction benefits you would expect, but the AWD XF and XJ are still very rewarding cars to drive – which was exactly our intention.”Jaguar says the AWD drivetrain will only be offered with the supercharged V6 engine because of its high torque output, ruling out its application with the smaller Ford-sourced 177kW/340Nm 2.0-litre turbocharged petrol engine available on the XF (and also used in the Ford Falcon EcoBoost).

This supercharged engine will almost certainly be introduced to local versions of the existing rear-drive range at the Australian International Motor Show in October, replacing the current naturally aspirated V6 and V8 units.

The direct-injected engine features a twin-vortex Roots-type supercharger mounted in the ‘V’ of the engine, plus electronically managed boost control that is said to improve operating efficiency by 20 per cent.

AWD versions sold overseas will feature a modified version of the ZF eight-speed automatic transmission, tweaked to accommodate a transfer case with active coupling, directing torque to a new front propshaft and front differential via a multiplate wet clutch.

Accommodating the bulkier architecture required Jaguar to re-engineer the front subframe, cross-member, engine mounts and exhaust system, while the front driveshafts have been relocated to run through the engine sump for a lower centre of gravity.

A new engine ECU allows it to communicate with the active transfer case, while the fuel lines, hoses and air intake have been modified, and a new engine undertray and heatshield are said to incorporate more sound-deadening to improve refinement.

AWD versions of the XF and XJ (both standard and long-wheelbase derivatives) are identified by ‘3.0 AWD’ badges on the bootlid.

The system will not be applied to the new XF Sportbrake wagon bodystyle, which will be offered by special order Down Under in rear-drive guise from later this year.