BMW X4 review - Engines, performance and drive
The X4’s powertrains are all excellent, but the six-cylinder diesels are a particular highlight
A cornerstone of BMW models has always been their superb engineering. Engines, chassis and driver aid technology always seem to sync with total precision, creating a feeling of indomitable solidity and high-class eloquence. This is something that permeates with the X4 too, despite its contrived form.
Fundamentally the X4, and X3 on which it is based, feel very similar to drive. In its latest iteration, the X4 has only marginally retuned suspension to go with its wider rear track depending on the suspension option specified, but it would take back-to-back comparisons to notice any variation. The result is that the X4 handles with impressive composure without feeling too compromised.
Yet despite the sporty handling, the X4 is still a comfortable car with a caveat or two. All UK models are fitted as standard with M Sport suspension, and while being firm the ride is always composed and well-damped. Things can get a little choppy if you upsize the wheels to the 20- or 21-inch option, but the optional adaptive dampers then cancel this out as they have a further ‘comfort’ setting, making them a worthwhile upgrade. That gives the X4 the ability to cope with broken urban roads, motorways and challenging B-roads with general ease.
M Performance models have a bespoke suspension tune that certainly makes the cars feel more stable, but also compromise on low-speed ride – especially considering it runs a standard 21-inch wheel. The flipside is more agile handling, which makes better use of the rear-biased all-wheel drive system.
The eight-speed automatic transmission is excellent in the X4. It shifts smoothly and quickly, while the separate drive modes mean the gearbox is able to change its shift points that improves better response or economy depending on the selected mode. Manual shifting is also possible, either by the paddles on the back of the steering wheel or by using the gear selector, which retains a joystick-style lever rather than the tiny switch found in most modern BMWs.
The X4 M Competition is a totally different animal to lesser X4s, with a much more boisterous personality. Its suspension design isn’t fundamentally different, but the geometry and setup is completely bespoke, with much higher spring rates designed principally to keep the engine’s immense performance under control. The ride quality, even in its softest damper setting, is extremely firm creating a daily driving experience that’s more akin to a hardcore supermini than midsize SUV.
The flipside is that the X4 M Competition has very impressive dynamics, with a tail-happy demeanour that’s even more driver-focused than rivals from Porsche, Alfa Romeo or Maserati. As such it’s very engaging, but we’d suggest you drive it first to make sure you can live with the compromises that go with it.
0-62mph acceleration and top speed
The 181bhp 2.0-litre diesel found in the xDrive20d is the most popular choice here in the UK, and performs very well in a variety of circumstances. Although it’s not as quiet as an equivalent diesel engine found in an Audi Q5, it’s both faster and more efficient, while also syncing better with its eight-speed automatic transmission. On paper, it will do 0-62mph in 7.9 seconds.
Moving up to the xDrive30d brings the additional performance and sophistication of a six-cylinder 3.0-litre diesel unit, with the further benefit of it being significantly smoother than the four-cylinder diesel. It also turns the X4 into a bit of a high performance sleeper with a 0-62mph time of 5.7 seconds, yet only results in a small penalty in terms of increased fuel consumption. The M40d model is quicker still, with the twin-turbocharged unit pushing the X4 from 0-62mph in only 4.9 seconds, with a very generous slog of torque making it feel even more rapid in-gear than the numbers suggest.
The X4 engine line-up welcomed mild-hybrid technology in 2020, with the aim of improving fuel efficiency and CO2 emissions. It features on all diesel models and allows the X4 to coast with the engine off at speeds below 99mph. The system will also shut down the engine when slowing down below 9mph, allowing it to harvest electrical energy.
The M40i features BMW’s 352bhp twin-turbocharged 3.0-litre petrol unit which is found in everything from a 3 series, to a Toyota GR Supra, Morgan Plus Six and even the Ineos Grenadier. Its straight-six configuration helps keep the engine smooth even at high revs, but being a petrol, the engine’s less torquey than the equivalent M40d and is arguably less suited to the X4’s SUV body. So despite having more power than the diesel, its 0-62mph time only equals the M40d at 4.9 seconds, while using significantly more fuel in the process. It is lighter on its feet, though, making the M40i a sweeter drive in corners.
The X4 M Competition uses BMW M’s heavily upgraded S58 straight-six petrol that produces 503bhp. It might start life as the same engine as the one found in an M40i, but these are two very different animals, with a comprehensive overhaul that from the top down that include impressive high performance technologies like 3D printed elements in the headers and forged engine internals. Despite the two-tonne weight figure, the X4 M Competition will rocket to 62mph in 3.8 seconds and on to a limited top speed of 155mph, which can be raised to 177mph with the optional M Driver’s Pack fitted.
In this review
- 1BMW X4 reviewThe BMW X4 offers a little extra style over its X3 sibling, but it's more expensive and sacrifices practicality
- 2Engines, performance and drive - currently readingThe X4’s powertrains are all excellent, but the six-cylinder diesels are a particular highlight
- 3MPG, CO2 and Running CostsFantastic economy numbers don’t quite make up for the high running costs associated with big SUVs like the X4
- 4Interior, design and technologyIt might be underpinned by an older generation of BMW design, build quality and interior tech is still excellent regardless
- 5Practicality, comfort and boot spaceThe X4 includes generous space for passengers and luggage, but the steep-sloping rear roofline means compromises have to be made
- 6Reliability and SafetyThe X4 includes a high standard of safety equipment across the range, although feedback from BMW owners could be better
- 7Used and nearly newA full used buyer’s guide on the BMW X4 covering the X4 Mk1 (2014-2018)