BMW 6 Series Gran Coupe saloon (2012-2018)

The respective model ranges of Mercedes, BMW and Audi are constantly growing as they aim to fill every gap in the market. The BMW 6 Series Gran Coupe (sometimes shortened to GC) is a product of this; it’s a luxurious four-door saloon that’s about the same size as a 5 Series, but with a sleek, coupe-style body. The GC is based largely on the two-door 6 Series, but has been made longer to make room for rear doors, proper rear seats and a bigger boot.

Although previously offered as a 630i with a 2.0-litre engine, petrol 6 Series Gran Coupe choices now consist a 3.0-litre six-cylinder 640i and 4.4-litre V8-powered 650i, both of which are twin-turbocharged and unlikely to disappoint drivers with a lack of power. The range-topping M6 Gran Coupe – which we've reviewed separately – takes performance to the next level, thanks to its 552bhp. Only one diesel engine is offered, a 3.0-litre six-cylinder twin-turbo the 640d, producing 313bhp and returning up to 52mpg.

Inside, the 6 Series Gran Coupe offers the usual BMW blend of sporty appeal, high-quality materials and luxury. All models get BMW’s iDrive infotainment system, which controls everything from the radio, sat nav and phone options to suspension settings, all from an simple-to-use rotary control on the centre console. Swathes of leather and wood can be specced to make your 6 Series GC a cosseting and stylish long-distance machine.

Unsurprisingly, the 6 Series Gran Coupe is a joy behind the wheel. It’s a heavy car, but it rides well and offers a great driving experience; all engines have plenty of shove, with lots of low-down power to make overtaking a breeze. The car is a comfortable motorway cruiser, but good fun on a twisty road, too – just as a BMW should be. For the ultimate in performance and driver appeal, although not quite matching the M6, the 650i M Sport takes some beating, with its twin-turbocharged V8, sports suspension and wide, grippy tyres.

All 6 Series Gran Coupe engines come with a stop-start system and BMW's eight-speed automatic transmission. The results are astonishing – the 640d diesel returns fuel economy of up to 52.3 mpg and CO2 emissions of 147g/km, while still covering 0-62mph in 5.4 seconds. Company-car users will find that it offers the lowest Benefit-in-Kind (BiK) tax rating of the range, at 30%.

The 640i petrol posts the same 0-62mph time, but uses far more fuel, with a combined figure of 37.7mpg. Emissions of 182g/km mean a BiK rating of 35%. The 650i petrol is unsurprisingly the least fuel-efficient of the bunch, but it's the first V8-powered BMW to emit less than 200g/km of CO2 – but it still sits in the highest 37% BiK band.

SE models tend to have slightly lower CO2 emissions due to their smaller wheels, so check CO2 figures carefully if first-year tax rates are an important consideration, because M Sport models can fall into higher bands on some models. All 6 Series Gran Coupe models cost £140 a year to tax after the first year’s CO2-weighted payment (usually rolled into the on-the-road price), but thanks to their £40,000-plus asking prices, all qualify for the additional £310 surcharge. This will bring your total tax bill to £450 a year the first five times you tax it.

For such a large car, the 6 Series Gran Coupe handles well. An optional active steering system turns the rear wheels slightly as well as the front wheels, which gives the steering a crisp and responsive feel.

Up the pace and the Gran Coupe feels balanced in the corners and lots of fun to drive. The 444bhp BMW 650i GC model is explosively fast, while the six-cylinder BMW 640i GC is also quick and thanks to the standard sports exhaust on petrol models, both sound fantastic.

But our pick of the range is the BMW 640d GC diesel, which matches the 640i's acceleration but uses much less fuel.

Variable dampers, fitted as standard, allow you to adjust the suspension, but even in its firmest setting the Gran Coupe is comfortable and quiet over long distances. Specifying BMW's Active Drive system adds active roll bars at the front and back – these stop the car rolling from side to side in corners.

It all adds up to a car that's stable and balanced whether you're cruising around town, heading down the motorway or driving quickly on a quiet country road. The interior quality is superb, while the seats are comfortable and hold you in place well. The 6 Series is still a sporty car, however, and won't match the comfort of a dedicated cruiser like the larger BMW 7 Series.

However, BMW tries to soften that blow with luxuries like BMW's ConnectedDrive, which has an on-board concierge service. That means drivers can call up a dedicated team of assistants and query anything from a technical issue to dinner reservations. If you need even more connectivity there's an optional wi-fi hotspot feature, together with wireless phone charging. BMW's 'remote services' became standard in 2018, allowing drivers to check their car's fuel level and location from a smartphone app, and even flash its headlights, lock or unlock the doors and set the ventilation while sat on the sofa.

BMW refers to the 6 Series Gran Coupe as a 4+1, as opposed to the 2+2 layout of the 6 Series Coupe. That means a fifth passenger can just about squeeze in, but because the centre seat is raised, there's limited headroom and it’s only really comfortable for short distances.

Rear legroom is generous, though, and unlike the Coupe, the GC's rear seats fold flat, boosting the narrow boot space from 460 litres to 1,265 litres. A ski hatch also lets you poke longer objects through with the seats in place.

All engines offered with the Gran Coupe have been tried and tested elsewhere in the BMW range – so major mechanical problems should be few and far between.

A huge range of optional safety equipment is offered, including a surround-view camera, night vision with pedestrian recognition, parking assistance, lane-departure warning, speed-limit display and a full-colour head-up display so you can keep your eyes on the road at all times.

A starting price of around £47,000 is more or less on par with German rivals like the Mercedes CLS and Audi A7 and it’s a similar story as you work your way up the range. Top-spec models find their prices treading on the toes of the Porsche Panamera and Maserati Quattroporte.

Two trim levels are offered in the UK – SE and M Sport – with the latter adding approximately £4,500 to the price. As standard, you get leather trim, sat nav, 18-inch alloys and heated seats, while M Sport adds 19-inch lightweight wheels, a stylish bodykit and sports seats. BMW’s xDrive four-wheel-drive system is available on 630d and 640i engines in both trims.