2018 BMW 6 Series Gran Turismo revealed, due for Australia this year

Measuring 5091 millimetres long, 1902mm wide, 1538mm tall, and riding on a 3070mm wheelbase, the new 6 Series Gran Turismo is 87mm longer overall than its predecessor. The width and wheelbase are unchanged, but the roof line sits 21mm closer to the ground.

That, along, with a lower rear deck that 64mm lower and a horizontal bulge above the rear wheel arches has significantly improved the car's proportions.

Compared to the current 5 Series sedan, the 6 Series Gran Turismo is 155mm longer overall with a 95mm longer wheelbase.

Thanks to its increased dimensions, boot space has increased from 500 litres to 610 with the rear seats up. When the rear seats are folded, the capacity increases to 1800L, an improvement of 100L.

When fitted active air flaps, an automatic rear spoiler and air breathers, the new car has a significantly lower coefficient of drag — 0.25 compared to the old model's 0.29 figure.

Based on the CLAR architecture used in the latest 5 Series and 7 Series models, the 6 Series Gran Turismo utilises an array lightweight materials. BMW claims the new hatch is up to 150 kilograms lighter than the outgoing 5 Series Gran Turismo.

In overseas markets, the initial engine range features two petrol motors. The 630i has a 190kW/400Nm 2.0-litre turbocharged four-cylinder motor with a 0-100km/h time of 6.3 seconds, and an EU fuel consumption rating of 6.6L/100km.

For those wanting a bit more oomph, the 640i features a 250kW/450Nm 3.0-litre turbo six-cylinder. The 640i is good for a 0-100km/h sprint in 5.4 seconds, or 5.3 seconds when equipped with the xDrive all-wheel drive system. Fuel economy is rated at 7.4L/100km in the 640i, and 8.2L/100km in the 640i xDrive.

At launch, the sole diesel model is the 630d, which has a 195kW/620Nm 3.0-litre turbo-diesel straight-six engine under the bonnet. It can dispatch the 0-100km/h standard in 6.1 seconds, or 6.0 seconds in xDrive guise. Fuel consumption is said to be 5.3L/100km in rear-wheel drive form, or 5.9L/100km for the all-wheel drive model.

All engine variants come with an eight-speed automatic transmission. The 630i is exclusively rear-wheel drive, while the 640i and 630d can be optioned with all-wheel drive.

Standard features include LED headlamps, self-levelling rear suspension, and electric tailgate operation.

Depending on the model, other available items include adaptive air suspension, active roll stabilisation, active steering, remote control parking, colour head-up display, massaging front seats, electric rear seat adjustment, and a 40/20/40 split-fold rear bench.

The iDrive system features a 10.25-inch free-standing touchscreen and a controller knob in the centre tunnel. Also available is Wi-Fi hotspot functionality, rear seat entertainment units, live traffic information, voice control with natural language recognition, wireless phone charging, and smartphone calendar and contacts integration.

Assisted driving features on the menu include active lane keeping assistance, lane departure warning, crossroad and wrong way alerts, and an active cruise control system that works in stop/start traffic and at speeds up to 210km/h.

The new BMW 6 Series Gran Turismo will make its global debut at the Frankfurt motor show in September before arriving down under during the fourth quarter of 2017. For Australia, the launch variant will be the 630i.

It's likely the 6 Series Gran Turismo will feature a price premium over its smaller and less sophisticated predecessor.

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