The 535i is a 3.0-litre petrol engine which uses two turbochargers to produce 306bhp. This is one of BMW's finest engines and is equally impressive in the GT with an immediate urgency across the rev range and a 0-62mph time of 6.3 seconds. Despite this it still manages to return a useful 32mpg along with acceptable CO2 emissions of 209g/km. The top engine is the mammoth 550i. For outright BMW 5 Series GT performance go for this model. Despite the name, this is actually a 4.4-litre V8 engine, but like the 535i uses twin turbochargers to boost power. As a result it produces 407bhp and is thunderously quick as you'd expect, accelerating from 0-62mph in just 5.5 seconds. The downside is economy of just 25mpg. All models come with the latest eight-speed automatic gearbox as standard which delivers incredibly rapid yet smooth shifts.
BMW's best engines are available in the 5 Series GT, starting with the 530d. This three-litre six-cylinder diesel engine is incredibly smooth and refined on the move plus with 245bhp along with immense amounts of low down pulling power, it can accelerate from 0-62mph in 6.9 seconds while still averaging 44mpg. That's even more impressive when you remember that the GT weighs around two tonnes. It can be a little noisy under hard acceleration, but overall is very quiet, especially on the motorway. The 535d is a twin-turbo version of the 530d and comes with 300bhp for 0-62mph in 6.1 seconds and astonishing low- and mid-rev acceleration. In mid-2012, BMW added the 520d that offers superb 53.3mpg and 139g/km carbon dioxide emissions as well as still serving up a fine drive and refinement thanks to its 184bhp.
While the larger engines appeal for their performance, it’s hard to see past the economy and emissions of the 520d model.
On the move the GT feels very much as BMW describes it - as a cross between a normal saloon and a 4x4. Its real forte is effortless motorway cruising which it does supremely well, feeling incredible stable and reassuring at high speeds. This is helped by the advanced rear air suspension which maintains a consistent ride height, whatever the road conditions.
On more demanding roads it can feel a little heavy and not as agile as a standard 5 Series, this is most noticeable when bringing the GT to a halt. But it corners incredibly well for such a big car with very little body roll and well weighted steering while there are impressive grip levels too. All models come with a system called Drive Dynamic Control which allows you to change the throttle response, steering feel, gear changes and the level of stability control.
There are three pre-set settings - Normal, Sport and Sport+ but you can also partly configure these yourself. A further system called Adaptive Drive is available as an option. This adds a Comfort setting with a softer ride.
The GT heralds the new generation of 5 Series models and this is reflected in the high class interior. Quality is superb, even by BMW standards, and all the buttons and switches feel upmarket. The design is bold, especially the large expanse of solid trim that spans the dashboard, yet the main controls are still simple to use on the move. The unusual stubby gear lever looks odd but is even easier to use than a normal automatic, while the electric parking brake frees up space on the high-placed central console.
The main stereo and sat nav (where fitted) functions are controlled through the iDrive dial, next to the gear lever. The system works well, but can take some getting used to initially. Thankfully the air conditioning controls are more traditional buttons and there are also switches on the steering wheel for controlling the stereo and trip computer.
One great feature is the head-up display. It's an optional extra and not very cheap, but it is very useful and projects the speed, as well as sat nav and trip information, onto the windscreen, so you don't have to take your eyes off the road.
At five metres long, BMW 5 Series GT comfort levels are surprisingly good because there's serious amounts of rear passenger room - in fact it's spacious enough to rival luxury limousines with enough room for even the tallest of passengers to stretch out. In SE models there are three seats in the back, but in reality it's much better suited to two, helped by the wide armrest that folds down from the central seatback.
The two outer seats also slide forward and back plus they can be reclined, ideal for a relaxing snooze on long journeys. Executive models come with a four-seat layout. The ride is excellent and there's barely any noise - either road or wind - even at motorway speeds. As you'd expect on a top BMW the seats are incredibly cosseting yet also supportive, although lumbar support is only standard on Executive models and optional on the SE.