• All X6s are quick – even the entry-level model
• The 3.0-litre model will be the best all-rounder for most
• Handling and steering are still up there with the best

If this car’s looks are less than subtle, then so is BMW X6’s performance. Even the least-endowed X6 xDrive 30d M Sport boasts of 260hp and a 0-62mph time of 6.7 seconds. Buyers can choose from three diesels for their X6s, but all come with BMW’s excellent eight-speed automatic gearbox which is smooth, quick-shifting and responsive to any manual inputs. 

Diesel engines

There’s a choice of three diesel engines: the entry-level X6 xDrive 30d, the X6 xDrive 40d and the mighty X6 M50d. The former is refined, smooth and offers more than acceptable performance – especially in the face of its efficiency levels. The latter engine is all you’ll ever need. Using the same basic 3.0-litre six-cylinder diesel engine as found in the X6 30d SE, but with three turbochargers, power is boosted from 254bhp to 376bhp – a 122bhp increase. Torque takes a similar hike, rising from 560Nm to 740Nm.

Mixed together, and fed to the four-wheel drive system through the also familiar eight-speed automatic transmission that allows the near two-tonne BMW X6 M50d to accelerate from 0-62mph in 5.2 seconds, or 1.5 seconds quicker than the X6 xDrive 30d SE – and more relevantly, faster than all but e fastest hot hatches on sale. It also adds another 12mph to the 30d’s 143mph top speed, the M50d electronically limited to the same 155mph as the petrol-engined model.

Despite all that mid-range punch, there’s a fair bit of bellow and bluster up top where the once muted grumblings of this straight-six diesel give way to a rather grating rattle. Dare we say it, but it almost feels like this triple-boosted 3.0-litre diesel is being stretched a little too far – a larger capacity diesel with another pair of cylinders doesn’t exhibit any such issues.

BMW insists that it handles more like a sleek sports car than a hulking great 4×4. Of course, even a company as clever as BMW can’t alter physics and with the X6’s considerable weight it’s never going to boast the agility of the firm’s M4 or Porsche’s Cayman.

Discontinued petrol engines

While you’ll only be able to buy an X6 with a petrol engine secondhand, the good news is that it’s fantastic. Not only is this turbocharged 4.8-litre V8 smooth, refined and capable of emitting a purposeful V8 burble under hard acceleration, but it’s also the fastest of the lot.

In fact 0-62mph only takes 4.8 seconds, and it generates those numbers with consumate refinement and a cultural exhaust note. Not only in terms of on-paper performance figures (455hp and 650Nm), for many, the sheer character of this engine will make it the enthusiast’s choice of used X6s.

Handling

• It’s a big, heavy car, but feels agile in corners
• Adaptive suspension is the best of both worlds
• Well set-up steering, lacking in feel

That said, BMW has done all it can to minimise the feeling of weight and size with the new X6. All models come with the firm’s Servotronic electric power-assisted steering, which adds weight to the rim the faster you go. It’s an accurate steering system, but hardly full of feel – if you want that, buy a Porsche.

Choose the M50d model and you’ll benefit from M Sport adaptive suspension. This Driver Performance Control allows users to select from Comfort, Sport and Sport+ modes (along with EcoPro which also affects gearbox and engine responses) to change the reactions of the suspension depending on the road situation and driver’s requests.

Combined with Active Roll Stabilisation, it means the X6 corners incredibly flat with little-to-no bodyroll detectable at anything less than extreme direction changes. In fact it’s not long before the X6 shrinks around the driver, and you soon feel like you’re piloting something much smaller and more agile. However, despite this trickery the laws of physics eventually come into play, and it’ll slide wide in corners.

There’s a choice of adaptive suspension systems available; Comfort Adaptive Suspension and Dynamic Adaptive Suspension, the former boasting rear air suspension units and the latter offering the Active Roll Stabilisation. Choose Professional Adaptive Suspension to combine the both and enjoy the best of both worlds.