Jaguar’s XF has received its mid-lifecycle facelift, four years after debuting as the C-XF concept at Detroit's North American auto show. In an attempt to keep the luxury sedan updated and capable of competing with BMW's 5 Series and Audi's new A6, XF's facelift was revealed at the New York auto show. The stylish Coventry luxury sedan gains new front and rear styling elements and some interior upgrades. There's a new entry-level turbodiesel engine too.XF design manager, Adam Hatton, was briefed to "turn up the visual volume and give a purposeful road presence," to Jaguar’s best-selling car. All XF models (including the high-performance XFR derivative) feature new LED embedded headlights, a less rakishly angled grille and reshaped lower bumper air-intakes. These design updates tally a more harmonized look, finessing the XF's styling to render a look closer to the new XJ. The facelift adds a liberal collection of LEDs to the XF’s taillights too.Inside, XF’s front and rear seats have been reshaped for even greater comfort whilst the infotainment system gains a 30Gb hard drive. DIESEL BECOMES THE FUTUREMechanically, the facelifted XF’s most surprising feature is the presence of Land Rover’s 2.2-litre Freelander turbodiesel engine. Designated i4D for its XF application, the Land Rover unit rolls a new camshaft, is boosted by a water-cooled turbocharger and features additional sound insulation around the bulkhead, alternator, turbocharger housing and starter motor to reduce acoustic cabin intrusion from the engine to levels acceptable to Jaguar owners.Why the need for a small turbodiesel? Jaguar predicts 60% of its XF facelift customers will option diesel power; as such the availability of an entry-level turbodiesel to augment the V6D (202kW/600Nm) is crucial to servicing projected customer demand. The upgraded Land Rover engine is good for 139kW and 450Nm, guaranteeing swift dynamics (it runs the benchmark 0-100km/h in eight seconds) and outstanding efficiency. Jaguar says its XF i4D will return an amazingly frugal 5.4 litres/100km.Both XF facelift diesel engine derivatives will drive their rear wheels courtesy of ZF’s outstanding eight-speed auto transmission - a drivetrain upgrade Jaguar claims has improved efficiency and responsiveness. With its ability to jump-shift from seventh to second gear, and having already proven hugely capable in BMW’s 5 Series, the ZF eight-speeder should prove a huge improvement over the XF’s current six-speed auto. Jaguar’s facelifted XF is slated to enter production by the end of July 2011.