The BMW 5 Series GT range comprises two petrol options – the 535i and 550i – and three oilburners 520d, 530d and 535d. The 550i has under the bonnet the same 444bhp V8 as in the X6 xDrive50i. It has a healthy 479lb ft of torque from 2000rpm, meaning plenty of low-end grunt. It's best described as deceptively quick; the numbers on the head-up display always register far higher than you expect, and the V8 is silky smooth all the way through to the red line.
The 3.0-litre, six-cylinder engine installed in the 535i was BMW’s first engine to combine high-precision direct injection with both mechanically driven variable valve timing and lift (Vanos and Valvetronic in BMW-speak) and a twin-scroll turbocharger.
Even though it’s only got one turbo, the new engine slots in where Munich’s twin-turbo petrol six might have in this particular model range, producing 302bhp and an incredibly accessible 295lb ft or torque, available all the way from 1200rpm to 5000rpm. It feels game, precise and surprisingly fast for a two-tonner; 62mph comes up in a hot hatch-besting 6.3sec. There’s abundant torque throughout almost all of the usable rev range, and urgent performance on offer whenever you need it.
Raw figures (0-60mph in 6.3sec and 0-100mph in 17.7sec) understate how effortlessly the 530d GT picks up speed in everyday situations. Maximum torque is available anywhere between 1750 and 3000rpm, an operating range that is easy to maintain with eight forward ratios.
And such are the adhesive qualities of the 275/35 rear tyres fitted to our particular GT (wearing those optional 20-inch wheels) that there is little drama involved with transmitting 398lb ft of torque to the road. Other than its performance, BMW’s 3.0-litre, six-cylinder diesel also impresses with exceptional refinement. Other than moments of full throttle, the engine note is just a distant, unobtrusive hum.
The 535d, meanwhile, serves up 309bhp at 4400rpm and a frankly monstrous 465lb ft from 1500rpm, while propping up the 5 Series GT range a four-cylinder 2.0-litre unit which produces 181bhp and 280lb ft of torque from 1750rpm, which makes its gutsy enough to lug around the big GT
ZF’s eight-speed gearbox, which is fitted as standard across the range, is difficult to fault, the gearshifts smooth and for the most part unnoticeable. There is a variety of different gearbox modes, accessible either by moving the gearlever to the left to select Sport mode or by switching Dynamic Drive to Sport or Sport+, but in truth Drive offers the best combination of poise and refinement.