The new model replaces the 5 Series GT as BMW shakes up its product portfolio

THIS IS THE BMW 6 Series Gran Turismo, a five-seat fastback that the luxury carmaker is unveiling at September’s Frankfurt motor show.

We could see if available here by the end of the year, but it’s more likely that BMW will save it for a debut at next year’s Singapore Motor Show.

The 6 Series GT replaces the 5 Series GT, with the new model designation implying that it’s been significantly upgraded over its predecessor.

It’s longer (by 87mm) and lower (21mm), for a more sporty (or, you like, less dumpy) silhouette than that of the 5 GT. The tailgate area is less bulbous, too, with rear of the car now 64mm lower.

Despite the more athletic stance, the 6 Series Gran Turismo offers 20 litres more room in the boot than the 5 did, at 610. Fold the 40:20:40 split read seats and you get an impressive 1,800 litres. That’s 100 litres more than before, and more than a Volvo V90 can carry.

The growth spurt might suggest that the new 6 will be a heavy lump, but BMW says it’s actually up to 150kg lighter than the 5 GT.

That should bode well for the driving experience, with even the slowest model taking just 6.3 seconds to hit 100km/h. That’ll be the 630i Gran Turismo, which has a 2.0-litre turbo four-cylinder with 258hp and 400Nm.

It consumes between 6.2 and 6.6 litres per 100km/h, depending on equipment levels. There’s an active rear spoiler to better manage airflow, helping to cut wind resistance and reduce fuel burn.

BMW is launching the car with a 3.0-litre diesel engine (630d) that’s good for 265hp and 620Nm, enough for 0 to 100km/h in 6.1 seconds (or 6.0 seconds with BMW’s xDrive all-wheel drive system fitted) but we wouldn’t put money on that model making it to Singapore.

Instead, the flagship for now will probably be the 640i GT, which has 340hp, 450Nm and can hit 100km/h 5.4 seconds. Fuel consumption for that is 7.0 to 7.4L/100km.

All versions have an eight-speed auto.

Inside, the car gets the latest cabin systems from the current 5 Series, so a touchscreen, gesture control and a tile-based home screen on the main display are new features.

Why buy this over a (cheaper) 5 Series? Apart from the idea that saying you drive a 6 Series makes you sound posh, there’s an elevated driving position, and the rear seats have more headroom than before, with electrically adjustable seats as an option.

Perhaps the real question is, what happens to the rest of the 6 Series range?

There’s talk that BMW will discontinue the Coupe and replace it with the upmarket 8 Series, seen here in concept car form. That would entail discontinuing the Convertible as well, but there would still be room in the product family for a four-door 6 Series, so the Gran Coupe would likely continue.

Meanwhile, BMW will introduce a baby crossover coupe called the X2 next year, with a giant seven-seat X7 to top off its Sports Utility Vehicle range.

The new models are part of an aggressive product onslaught intended to wrestle the number one spot in luxury car sales back from Mercedes-Benz.

If you were wondering why a 6 Series Gran Turismo even exists, there’s your answer.