BMW X6

Ignore BMW’s claim that the X6 is the world’s first Sports Activity Coupé. As with most self-generated name tags, it doesn’t make a lot of sense to the average car buyer. Think of it as an X5 coupé, and things become a little clearer. But why, when that model is riding high in the sales charts, does the world need a slightly more expensive, yet less practical, version?

Well, according to BMW, the X6 exists because the luxury 4x4 sector is becoming crowded. While the customer base is expanding, so too is the number of makers in the class. The result? Everyone is selling fewer cars, despite the market growth.

Bosses reckon the only way to move sales forward is to offer something nobody else does – and the X6 fits that brief. Built on the platform of the current X5, it’s effectively a sportier version of one of the world’s favourite premium SUVs.

It’s impossible to discuss the X6 without focusing on the design. If you thought BMW was starting to mellow out after years of producing quirky shapes, think again. The X6 is as bold as they come, with unconventional angles everywhere. But look at the car’s profile, and it’s clear what’s going on. While the bottom half is little changed over the X5, the top bears a resemblance to the 6-Series coupé.

Inside, the X6 borrows more X5 design features, and aside from the knee braces on the side of the transmission tunnel and the chunky gearshift paddles, it’s all but identical up front.

However, the newcomer’s coupé aspirations are more obvious in the back. The dipping roofline eats into headroom, while BMW’s determination to make the X6 a four-seater has seen the centre seat replaced by a large plastic tray. It’s neat enough, but you have to wonder whether the firm couldn’t have found a way to offer an occasional perch and seatbelt for a third rear passenger.

While we’re on the subject of questionable design, the high back end gives the X6 all the rearward vision of a supercar. With the bottom edge of the hatch window well over a metre high, it’s not only bollards and low walls that drivers need to be wary of – the average family car can be lost in the vast blind spot directly behind the BMW. Wisely, parking sensors are standard on all X6s.

It isn’t all bad news on the practicality front. There’s more headroom in the back than you’ll find in either the Mercedes or the Audi, while the 570-litre boot is bigger than anything else in this test – although it’s down by 25 litres on the X5’s.

The X6 has two new petrol engines: a 306bhp 3.0-litre V6 and 408bhp 4.4-litre V8. But the diesel line-up is more familiar – and the 3.0-litre twin-turbo straight-six in this flagship 35d is an Auto Express favourite. It’s bursting with torque throughout the rev range, and makes light work of the car’s hefty 2,110kg kerbweight.

A number of chassis tweaks set the X6 apart from the X5. The ride height is lower, and it’s the first model to be fitted with BMW’s Dynamic Performance Control. This new system claims to maximise drive when cornering by constantly monitoring the torque split from side to side.

In practice, it’s hard to detect it working, but what we can say is that the X6 loves the open road. Although its sheer bulk limits progress on narrow lanes, the steering, body control and ride quality are all first class. It’s just worth bearing in mind that our test car came with £2,300 adaptive dampers, active steering (£910) and a Dynamic Package with sports suspension (£3,230). How the X6 feels without this kit remains to be seen.