BMW’s X5 twin-turbo diesel treat

BMW Australia is poised to introduce what it claims is the world’s most powerful six-cylinder diesel engine to the all-wheel drive X5 range.

In the UK this weekend, BMW GB is featuring the same engine with the launch of “the world’s first diesel-powered luxury 2+2 Grand Tourer” in the form of the 635d.

While Australia will not get the new diesel 6 Series Coupé and Convertible models, there is every chance we will see the awesome twin-turbo diesel engine here under the bonnet of the X5 early next year.

The 3.0-litre turbo-diesel engine, which originally debuted in Europe in the 5 Series, has an all-aluminium crankcase and a third-generation common rail fuel-injection system.

It produces some 213kW of power and 580Nm of torque, enabling the new 635d Coupe to accelerate from rest to 100km/h in just 6.3 seconds. The heavier Convertible is three-tenths slower.

Fitted to the X5, expect acceleration to be only half a second or so slower than the current 4.8-litre petrol V8-engined model, which does the sprint in about 6.5 seconds – but the twin-turbo diesel will use less fuel, produce lower emissions and carry a considerably lower price tag.

The European-market BMW 635d (left) is being launched as part of a facelifted 6 Series range, with a revised tail, wider air intakes, LED tail-lights and a new six-speed automatic transmission.

The lightly revised 6 Series will appear at the Australian International Motor Show in Sydney next week before hitting local showrooms in December.

BMW is the leading supplier of luxury diesels in Australia, with a narrow lead over Mercedes-Benz, but does not believe there is sufficient demand here for a 6 Series diesel.

While diesels account for a high percentage of SUV sales – some 65 per cent in X5 and 44 per cent in the smaller X3 – only about 10 per cent of passenger cars are ordered with diesels in Australia.

With 6 Series sales here running at only about 200 units a year, the numbers simply do not add up.

To highlight how modern cars have developed, reducing emissions and improving fuel consumption, BMW UK will showcase the new 635d alongside the first generation M635CSi from 1986 at the SMMT (Society of Motor Manufacturers and Traders) ‘Evolution of the Car’ driving event on 9 October.

The facelifted 6 Series Coupe and Convertible range, which will continue to be powered by a 5.0-litre V8 petrol engine in Australia, feature a revised headlight arrangement incorporating LED technology and clear lenses, and a new style of front valance.

The vertical struts on the front spoiler have been repositioned to accommodate a different shape of air intake for the car and the kidney grille is larger compared to the current model.

At the rear, the lower reflectors have been enhanced as part of a redesigned rear bumper to emphasise the wide track, while a high-level brake light is now integrated into boot lid lip.

New alloy wheels in 17-, 18- and 19-inch sizes complete the exterior changes.

Interior changes include the introduction to the Convertible of BMW’s SunReflective Technology leather, which has embedded pigments in the leather that reflect infra-red radiation in the sunlight and can reduce leather temperature by as much as 20 degrees.

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