The XJ's sense of effortless performance is taken to an even higher level thanks to the latest-generation V6 diesel. Smoother and quieter than ever, this power unit gains even more sophisticated common rail and turbocharging systems, boosting power and torque from 275PS/600Nm to 300PS/700Nm. The extra torque not only improves responsiveness, it also delivers greater efficiency, helping to reduce emissions from 159g/km to 149g/km CO2.
New eight-hole piezo injectors ensure that fuel is delivered into the combustion chambers with even greater precision and control, while increasing the maximum injection pressure to 2,000bar ensures even better mixture formation. All of this leads to reduced fuel consumption and emissions, and higher output.
The innovative parallel-sequential boosting system receives more aerodynamically-efficient turbochargers, while the primary turbo now features highly-advanced ceramic ball bearing technology: the reduced friction means even better launch performance and transient response because torque builds up even more rapidly than before.
Engine efficiency is improved too. A switchable coolant pump and dual-stage oil pump ensure faster warm-up and reduced parasitic losses. And the exhaust gas recirculation (EGR) system now features a cooled low-pressure circuit in addition to the high-pressure circuit: this enables inherently low emissions of oxides of nitrogen (NOx) as well as reduced pumping losses across a wider range of the engine's operating map.
Complementing the improved EGR system is a selective catalytic reduction (SCR) system. Injecting a urea solution upstream of a highly-efficient SCR catalyst converts NOx into nitrogen and water, ensuring that the new XJ meets Euro 6 exhaust emissions regulations.
The petrol engines: Powerful, refined, and efficient
The new XJ also offers the familiar range of all-aluminium inline-four, V6 and V8 petrol engines. All feature direct injection, variable valve timing, forced induction and intelligent stop-start systems to deliver high performance with remarkable efficiency.
The 240PS/340Nm 2.0-litre four-cylinder benefits from a low-inertia turbocharger to match the driveability of larger naturally-aspirated engines but with improved fuel economy.
The 3.0-litre supercharged V6 develops 340PS/450Nm and is available with rear- and all-wheel drive. Characterised by its linear power delivery and free-revving nature, this remarkable engine also delivers a unique soundtrack thanks to meticulously-tuned intake and exhaust systems.
The top engine option remains the 5.0-litre V8. Offered in 470PS/575Nm, 510PS/625Nm and 550PS/680Nm ratings, this exceptional engine delivers all of the performance promised by the XJ's dramatic styling.
Selecting the best: Eight-speed automatic transmissions
All powertrains feature a specifically-optimised eight-speed automatic from ZF. Each has been developed to provide the perfect balance of unrivalled launch performance, shift comfort, dynamics and efficiency.
Two variants of the 8HP transmission family are offered in the new XJ: the familiar 8HP70 transmission and the lighter, more compact 8HP45.