What's this?
BMW's fourth attempt at the 'sports activity coupe', but we're going to refer to it as a coupe-SUV from now on, because 'SAC' just looks deeply unfortunate. Despite BMW diversifying the SUV breed as far back as 2008 with the
original X6, there hasn't exactly been the automotive equivalent of a gold rush to this often-pilloried market sector. BMW remains the foremost purveyor of the things, following up the X6 Mk1 with 2014's first-gen X4 (based on the second-generation X3) and then replacing the larger X6 with an
all-new model in 2015 - but, aside from Mercedes, which challenges both X4 and X6 with (respectively)
the 2016-launched GLC Coupe and
2015's GLE Coupe - no other manufacturer has ever felt the need to follow BMW's suit.
This is mainly because there's a seam of trenchant criticism among the petrolhead fraternity, which rails against the sheer effrontery of trying to blend the lithe sportiness of a coupe with the chunky practicality of an SUV. Can't be done, say the naysayers. The resulting abomination is simply way too compromised and ugly to be worth any serious consideration.
BMW, though, would nonchalantly shrug its shoulders, as it clearly believes in the formula. It sold around 50,000 units per annum globally of the X4 Mk1 during its slightly-less-than-four years on sale, so similar numbers from the Mk2 would be most welcome. And so far, more than a quarter of a million X6s have been shifted worldwide, proving there's public appetite for these things. Even if some people abhor them.
So, here's what's known as the 'G02' X4, which goes along with the
G01 X3 upon which it is based. BMW is launching the X4 with five drivetrains, four 'regular' turbocharged petrol and diesel engines (all with four cylinders) and a sole M Performance derivative with a six-pot diesel motor. These will be badged xDrive20i, xDrive30i, xDrive20d, xDrive25d and M40d, in turn, and in quarter three of this year a 3.0-litre, six-cylinder diesel will join the ranks (the xDrive30d) while another hot X4 will be added too, the M40i, using the same 360hp turbocharged petrol engine as
its X3 analogue. In a case of 'a little give and take', the X4's M40d powerplant will subsequently appear in the X3 line-up... if you're still following all of this.
Anyway, as of writing only two engines of the launch choices are available in the UK, in the form of the xDrive20d and the M40d. The former engine has three trim levels, running Sport, M Sport and M Sport X, while the latter variant gets a high-grade specification all of its own. In terms of the general brushstrokes of the X4 family, the new model is up to 50kg lighter than its predecessor and it has a 30mm wider rear track, too. It has grown in all dimensions bar height (where it's 3mm lower than the old X4), which is to the benefit of interior space - 54mm in the wheelbase results in 27 additional millimetres of legroom in the back of the G02. The M Sport suspension from the G01 X3 has been taken and recalibrated (including where adaptive dampers are specified, either as an option or standard kit) to suit the sportier nature of the X4 and its lower ride height, while the electrically power-assisted steering (EPAS) has also been tweaked to suit. The coupe-SUV has a slippery, 0.30Cd aerodynamic shape (X3 = 0.33Cd) and this M40d variant also enjoys uprated M Sport brakes and an M Sport locking differential on the rear axle. In short, BMW wants you to know that the X4 is a serious bit of kit, not just an X3 with a bit less rear headroom.
So, before we find out whether that's the case, a quick word on the X4's looks and practicality. Dealing with the first of these... we like the BMW. Not just 'we can tolerate its appearance if we don't look directly at it for too long', but we genuinely think it's among the better-looking SUVs out there, coupe or otherwise. While we'd stop short of calling it beautiful, the sleeker rear-end of the X4 is its strongest aspect, because it no longer looks as needlessly hunchbacked as some of the coupe-SUVs that have gone before. Granted, glitzy Flamenco Red paint, M Sport bodywork and some whopping 20-inch alloys give it extra presence, but having seen a more modestly specified xDrive30i in Sophisto Grey Xirallic on the same gig, we know that the X4 looks good no matter what its spec.
And it'll function as a family car. Those rear seats are indeed roomy enough for two six-footers to get comfortable back there, although the centre pew is - as ever on four-wheel-drive machines - limited in terms of foot room by the X4's longitudinal transmission tunnel. Further, the seats' backs split 40:20:40, giving rise to a boot with an ultimate capacity of 1,430 litres; that's 170 litres down on what you'd get in an X3, but still pretty decent and 30 litres more outright cargo space than the old X4 possessed. With all the seats in place, the boot is up 25 litres on the old X4's at 525 litres, which is just shy of the X3's 550 litres, and access to the loading area is via an electrically-operated tailgate on all models.
How does it drive?
Excellently for any SUV, and certainly deserving of the manufacturer's claim that it's sportier and more rewarding than an X3. Which, in itself, is a pretty nice 4x4 to steer. Anyway, the X4 M40d has the 326hp/680Nm twin-turbo variant of the 3.0-litre straight-six diesel and, driving all four wheels via the unimpeachable eight-speed Steptronic Sport gearbox through faster-acting xDrive, the performance is electrifying. At anything below 100mph - relax, speed police, we drove it on track... - it just picks up and goes, hard, as the result of any sort of meaningful throttle inputs. There's also a nice, meaty snarl to it, which (if we have one acoustic regret) becomes a little too synthetic in note when the BMW's in Sport or Sport+ modes.
But yes, for a 1.9-tonne diesel SUV to move with such alacrity like this, you have to give the drivetrain the utmost credit otherwise. And the same goes for the refinement. Again, it's not a flawless report card in this regard, as you'll be quietly reminded of the 20-inch wheels nestling at each corner of the M40d by the occasionally firm-edged ride on poorer surfaces. Oh, and there's some elevated tyre noise in such circumstances as well. However, for 95 per cent of the time, the ride on the X4 is incredibly impressive, given its tauter-handling remit, and the noise suppression is exceptional. Sub-3,000rpm, the engine is practically inaudible, the gearbox in Comfort mode slushes in shifts utterly imperceptibly and that smoother exterior contributes to an almost total lack of meaningful wind noise. So, if you want to use the M40d as a serene family SUV, it should be perfect for such a task - as long as you don't live in an area fabled for washboard road surfaces.
Yet it's the handling which is the best feature of the M40d. Again, with one hand the car giveth and with the other, it taketh away, as the weighting of the steering is borderline unpleasant in Sport and Sport+ modes - it's just ludicrously heavy, which doesn't really add anything to either its accuracy or its consistency, instead masking what feedback the BMW possesses. Thankfully, the steering set-up is actually very good in other respects, so if you can tutor yourself to filter out the sheer heft you're using just to muscle the X4 into medium-speed sweeping bends (and you can, after a few miles of getting accustomed to it), you realise there's a joyous chassis underpinning this high-riding coupe.
It grips ferociously, with understeer only marginally evident if you're completely ham-fisted with the SUV on corner entry/exit. The adhesion it displays means you lean on it more and more, whereupon you find the body control is pitched just right for something 1.6 metres tall - it squidges a little on its adaptive dampers, but that's not a bad thing as it clearly conveys the weight transfer process that's going on during rapid cornering.
The best thing, though, is the liveliness of the rear axle. The diff isn't active if the ESC system is wholly engaged and it becomes part-active with the ESC relaxed into its halfway house setting, but switch the electronics off and the diff does all the dirty work of apportioning torque. Whereupon you find that, with a decent slug of throttle in Sport/Sport+ modes, a low gear engaged in the transmission and a tight corner to play with, you can get the X4 M40d to oversteer. It's gentle, tweak-of-the-tail stuff rather than grunting, great slides with smoke billowing off the rear rubber, but there are very few four-wheel-drive SUVs that can do any such thing, no matter what driving provocation you sling their way.
And so, when you start linking all of the above together - the epic powertrain, the supple body control, the sharp steering (weighting notwithstanding) and the throttle-adjustable chassis - what soon happens is that you spend 20, 30, 40 minutes on a challenging road, throwing the car about and generally having a ball... and you clean forget you're in an SUV. Surely, then, that is the design brief of the X4 hit squarely on the head?
Verdict
There are people who will never be convinced by the brilliance of the BMW X4 M40d, no matter what we write about its merits. But such snooty types will be the ones missing out. While there are niggles with the X4, like its heavy Sport steering, its (very) occasionally crunchy ride and its sometimes-synthetic engine note (which isn't even to mention the £55,000 expense of the thing nor the feeble rear view afforded by that letterbox screen at the back), it's also undeniable that it has an excellent chassis, top-grade refinement, an impressive level of practicality... and, yes, strikingly appealing looks. All in all, as performance SUVs go, the X4 M40d is undoubtedly one of the very finest ones.