BMW X4 M40i 2018 Review

What price 'M'? That's the question I ask myself after noting that the BMW X4 M40i is very nearly $10,000 more than the superseded X4 xDrive35i. Both cars come with six-cylinder engines, but the newer vehicle – tested for this review – produces significantly more power and torque in a package that's larger, but little heavier.

The BMW X4 M40i also comes with an M Sport rear differential and M suspension, an extra airbag, improved driver-assist (active safety) kit, bigger alloy wheels, fold-in mirrors and heated front seats, to name but a few items. So the value is there, it might be said.

With its M powertrain and underpinnings, the X40 M40i certainly is fun to fling around. However you cut it – in a straight line, under brakes or in corners – it's quick. Steering response is immediate in Sport mode and the X4 can be placed precisely on the road, thanks in large measure to steering feel.

But it didn't feel much quicker in the turns than the 20d and 30i variants of X4 I had driven in previous weeks. And the ride comfort sacrificed for the X4 M40i's dynamic ability is a big concession.

Even on freeways the six-cylinder X4 jiggled and pitched, and it also crashed over the odd pothole on a country road. The suspension is tied down hard and the run-flat tyres are unyielding as well. It's really a car for lovers of the M badge – and they'll forgive this particular X4 its uncompromising nature.

Even from among those who welcome a little more comfort, the BMW X4 M40i will still draw a crowd with its superb powertrain. The inline six is subdued in Eco-Pro or Comfort modes, but its character is transformed in Sport mode, offering power delivery that positively sparkles. All the while the engine is pressing you back in the seat, the exhaust note is present as a persistent howl, capped off with some pops on the overrun.

The transmission is a typically excellent effort from ZF and BMW for its matching to the engine. Generally smooth, the automatic shifts gear responsively using the paddles.

When driving more sedately, the mild-hybrid brake energy recovery and coasting functions were both effective in saving 'fuel kilometres', as was the idle-stop system, but the powertrain, brakes and idle-stop were frequently at odds with each other, as we've reported for other X4 models during the local launch.

Attempting to bring the X4 to a gentle halt was confounded by the hair-trigger impulse of the idle-stop system – restarting the engine at the very first sign of the driver lifting the foot off the brake pedal, however lightly. It's annoying and makes a pig's breakfast of driving for the comfort of passengers while trying to save fuel.

Despite that, the X4 M40i proved fairly economical when cruising. On a 70km test loop the X4 posted a fuel consumption figure of 11.2L/100km, and in urban commuting the X4 was frequently using fuel at a rate above 12L/100km. But over longer drives – mostly open-road cruising to Geelong or Melbourne Airport – the X4 was posting a figure as low as 9.0L/100km.

The BMW was very quiet at speed or running up to the built-up area limit and the 21-inch Pirelli P-Zero run-flats were not as noisy as expected on coarse-chip bitumen.

Over extended touring during the week the BMW X4 M40i was the sort of vehicle you could literally drive for hours and still feel fresh at the end of the journey – provided the journey was on smooth roads.

The driving position is sensible and easy to set up for optimal comfort and situational awareness. Very well shaped front seats were a boon for long drives in the country, and the cushioning provided about the right measure of firmness for support, with an extendable seat base as a bonus.

The instrument display goes through an interesting visual routine at start-up, but is otherwise a common example of BMW design ergonomics. It was a little surprising to learn that there was no wiper for the tailgate in the X4.

Inductive charging was very useful to have for those occasions when one's spouse had borrowed one's recharging lead for the smartphone.

Voice recognition for entering new addresses in the satellite navigation frequently endeared itself to users, and having the car and phone chatting together meant we could relocate the X4 easily after parking it in an unfamiliar part of town.

Using the fuel-saving Eco-Pro led to the windscreen fogging up on cold mornings, unless the climate control was set to the maximum demist setting. In fact, the climate control system (even with the 'auto' setting enabled) allowed the windscreen to mist up during a mild (16.5°) evening drive.

Accommodation in the rear of the X4 M40i was fine for adult-level legroom and toe room (under the front seats). But as with other X4 models, the roofline is low over the rear doors and the sunroof diminishes the available headroom for adults of average height. Passengers have cup-holders in the folding rear centre armrest and a very generous bottle-holder in each of the rear door bins. These will securely stow a 750ml bottle.

In spite of its sleek-ish rear end, the X4's boot is a relatively practical load space, with additional storage under the hinged floor, which is supported by gas struts. There are finger pulls just inside the tailgate aperture to flip the 60:40 split-fold seat forward for larger load volume.

Over the course of the week, the X4 was plagued by a persistent squeak in the driver's seat and a rattle from the front passenger seat.

With all the pros and cons listed on its scoresheet, the X4 M40i left me with mixed feelings. The performance and presentation were outstanding and it was comfortable and quiet in various ways, but there enough niggles to offset the highlights.

And that ultimately makes it a car for dedicated BMW six-cylinder fans more than for the average Fred.

How much does the 2018 BMW X4 M40i cost?
Price: $111,850 (as tested, drive-away with metallic paint for $1950)
Engine: 3.0-litre six-cylinder turbo-petrol
Output: 265kW/500Nm
Transmission: Eight-speed automatic
Fuel: 9.2L/100km (ADR Combined)
CO2: 210g/km (ADR Combined)
Safety rating: Five-star Euro NCAP (2017)