There will be three engine options at first: 630i and 640i petrols and a 630d diesel. Two trim levels will be available: SE and M Sport; the latter comes with chunkier bumpers, more prominent sills and larger wheels and tyres.
Prices will start at £46,810 for the 630i GT SE and rising to £57,570 for the 640i xDrive GT M Sport.
Although the GT will initially be part of a four strong 6 Series line up, alongside the Coupe, Cabriolet and Gran Coupe, those models will be phased out in the next two years, leaving the GT as the sole 6 Series model.
What’s new on the BMW 6 Series GT?
The 6 Series GT has bolder front end styling and a more shapely rear than the 5 Series GT, which was criticised for looking bulbous at the back. In comparison to that car, it is longer and not as tall.
It is 150kg lighter than the 5 Series saloon due to its new platform and greater use of aluminium and hot-formed high-strength steel in its body structure.
Rear air suspension with automatic self levelling is standard, but there will be the option to upgrade to all-round air suspension. Like other BMW models, rear wheel drive will be standard but higher end 6 Series GT models will be available with optional four-wheel drive and active rear steering.
What engines will the BMW 6 Series GT come with?
It will use some of the petrol and diesel engines already offered in the 5 Series line up; they will only be offered with an eight-speed automatic gearbox.
The smallest petrol engine, the 630i, is a turbocharged four-cylinder unit that is claimed to do 0-62mph in 6.3sec yet achieve official fuel economy of 45.6mpg. Its CO2 emissions are quoted as 142g/km.
Next in the line-up is the 640i, the latest version of BMW’s turbocharged 3.0-litre in-line six-cylinder petrol engine. In the four-wheel-drive XDrive GT it completes the 0-62mph dash in 5.3sec, sips fuel at a rate of 36.7mpg and has CO2 emissions of 177g/km.
The only diesel available at launch will be the 3.0 six-cylinder 630d, which does 0-62mph in 6.1sec and has official fuel economy of 57.7mpg and emissions of 129g/km.
More engines will be added in 2018, including an entry-level four-cylinder 620d.
It’s also possible that BMW will offer a pair of scorchingly fast M models: a M550i with a twin-turbocharged 4.4-litre V8 engine and a M550d which will have a quad-turbocharged 3.0-litre diesel.
The last model to join the line up will be a plug-in petrol-electric hybrid called the 640e. It will combine a 2.0-litre petrol engine with an electric motor.
What’s the BMW 6 Series GT like inside?
Inside, the 6 Series GT is very similar to a 5 Series saloon, but with front seats that are positioned higher up and rear seats that can be ordered with optional electrical adjustment.
A 10.3-in touchscreen infotainment system with voice and gesture controls is offered as an option.
How much will the BMW 6 Series GT cost?
Prices for petrol models will start at £46,810 for the 630i SE and £53,970 for the 640i xDrive, with a premium of just under £4000 for M Sport versions. Diesel prices range from £50,665 for the 630d SE to £56,605 for the 630d xDrive in M Sport trim.
Watch our video review of the 6 Series Coupe
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