Ah, time for the 5 GT update?

Em, no, this is the 2018 BMW 6 Series GT - or Gran Turismo to give it its full name. But you're partly right, as this car replaces the 5 Series Gran Turismo. So that means a four-strong 6 Series line-up now, made up of the two-door Coupe, the four-door Gran Coupe, the 6 Series Convertible and this, the 6 Series Gran Turismo. Keeping up?

Maybe... Why the name change?

BMW is moving the model further upmarket to better suit its original concept, which is that of luxurious lounging room inside and loads of luggage space all wrapped up in a body style that is deemed to be more stylish in some markets than the Touring estate. To that end, there are frameless doors all-round, alloy wheels of up to 21-inch diameter and a vast number of individualisation options inside and out to make the 6 GT as special as any 7 Series above it.

So what's new?

Well, the 6 Series Gran Turismo is a good bit longer (87mm) than the 5 GT for a start, though it's the same width and 21mm lower. That's to the benefit of aerodynamics and BMW has managed to increase headroom a little thanks to the redesigned cabin. The boot, at 610 litres, is a useful 110 litres more capacious than before and BMW reckons there's room in the back seats for three adults or child seats. Look closely at the pictures and you'll see a neat 'GT' motif in the doors too.

Up front, the 6 Series Gran Turismo is clearly from the same high class school of interior design as the new 5 Series and the 7 Series, with a 10.25-inch display screen that can be controlled by touch, gesture, voice or the usual iDrive rotary. A fab head-up display is optional, as is a kicking 1,400-watt Bowers & Wilkins sound system.

And what's under the bonnet?

When the 6 GT goes on sale at the end of 2017 the price list will feature 630i, 640i and 630d variants, all featuring turbocharged engines and an eight-speed automatic transmission, all limited to 155mph and the latter two available with xDrive four-wheel drive. The 630i is propelled by a 2.0-litre four-cylinder petrol unit making 258hp and 400Nm of torque. BMW quotes a 0-62mph time of 6.3 seconds. The 640i can better that by a full second thanks to 340hp and 450Nm of torque from its 3.0-litre six-cylinder engine. The 630d's engine is also a straight-six and though it's a little slower against the clock to 62mph (six seconds dead) than the 640i, with 265hp, it should feel the most effortlessly fast thanks to a massive 620Nm of torque. Obviously it'll be the most economical model.

Buyers can upgrade the chassis with active roll stabilisation, adaptive damping and rear-wheel steering, though all cars come with self-levelling rear air suspension as standard.

When can I see it for myself?

At the Frankfurt Motor Show this autumn, where the 6 GT makes its world debut. It goes on sale shortly after.

Shane O' Donoghue - 13 Jun 2017