Highly anticipated, but also very controversial. Can the all-new BMW 4 Series prove that beauty is more than skin deep? We test the new 420d to find out.

The BMW 4 Series has a far longer history than you might imagine. A Google search tells you that there was only one previous generation, but that’s because it used to be dubbed 3 Series coupe – because that’s basically what it is. Either way, the now renamed sportier take on a 3 Series has always been a contender for class leadership, however, the all-new 4 Series is arguably BMW’s most controversial car in a generation. The question is, can the world get past that grille?

Let’s kick off with that design, because it would be unfair to characterise this car by its whopping cheese grater alone – looks are subjective after all. The new 4 Series is actually a far more elegant design than before. Gone are many of the sharp creases that gave its predecessor a more aggressive tone, instead this car finds favour with soft edges and flowing lines. It still hosts recognisable traits such as those prominent shoulders, but its teardrop roofline melts away more subtly and the car projects a more sophisticated look overall. Our M Sport test car – now the standard trim – featured sharp LED lights, sporty bumpers and 18-inch alloy wheels.

This specific BMW 4 Series is also in a rather stealthy specification, something that somewhat hides those voluminous kidneys. I’m still not sold on them, although many of my colleagues have grown used to this preview of future BMW design language. Love it or hate it, this look is here to stay and it’s something that’ll likely be accepted by the masses over time. Maybe, I should just ‘get with the program.’

The interior is much more familiar, in that it is BMW’s traditional blend of high quality materials, sleek design and strong ergonomics. Leather and aluminium trims the cabin, with the former narrated by neat blue stitching on this car. As M Sport is the new standard, all cars come with luxuries such as supportive sports seats, a 10.25-inch infotainment system, leather, heated seats, snazzy digital cockpit instrumentation, reversing camera and three-zone air-conditioning. Yous sit cocooned in premium design with every button and switch easily falling to hand. In short, the front passenger’s cabin execution is excellent.

Sitting at the centre of the dashboard is the latest incarnation of BMW’s iDrive infotainment system. The 10.25-inch screen can be commanded by touch, but also via a physical rotating dial and series of shortcut buttons – ideal for use on the move. Menus are logically laid out, each filled with crisp and clear graphics. This really is amongst the best, if not THE best, infotainment systems out there. Additionally, it will also play nice with your smartphone, be it an Android or Apple device.

Rear passengers receive a surprising amount of leg room, but headroom is compromised by the sloping roofline. Realistically, these rear seats are destined for children or occasional use for short trips. Boot space it pretty good, though… 440-litres means there’s plenty of space for a suitcase or two.

Our BMW 4 Series is a 420d, not the sexiest engine choice, but likely the one that will appeal to more people than a sporting petrol model. Under the bonnet is a 2.0-litre turbocharged diesel engine that’s paired with a mild hybrid system to keep this motor the right side of European emissions laws. It produces 188bhp and 400Nm of torque, meaning that it retains a fair amount of poke. This power unit is connected to an 8-speed automatic transmission and BMW’s xDrive all-wheel drive system. Combined it all equates to a 0-62mph dash of 7.4 seconds and a top speed of 147mph, so not exactly slow.

When behind the wheel of the new 4 Series, the first thing that hits you is just how refined it is. The engine in motion melts away into the background to the point of being near silent, with a touch of road noise being more audible than the diesel at work. Acoustic glass keeps external noises at bay, and there’s very little vibration from the outside world translated into the cabin. You immediately get a sense that this is a car you could comfortably cover large distances in.

As standard, the 4 Series comes with a rather sporting suspension setup, however, this car was also optioned with adaptive dampers. Via the selectable drive modes, you can change the car’s demeanour, but in some car these alterations to steering weighting and throttle response can be a bit superficial. In the 4 Series, there’s a commendable change in attitude. In comfort we were surprised at just how impressive the ride of the sports coupe was. Driving over some pretty poor surfaces revealed commanding damping and great isolation from the rutted road below. Switch it into Sport and things become firmer, but body control and the additional accuracy that heavier steering brings is welcome. A nice feature in this car’s cap is the ability to customise these settings, something that can result in nice precise steering, but a compliant ride.

Driven with gusto, the 420d’s engine does display a touch of turbo lag, however that momentary flicker is then met with robust torque. All-wheel drive traction and the strong progress of the engine would have you believe the car is faster than its stated 0-62mph time. The 8-speed automatic gearbox is silky smooth when left to its own devices, and is responsive when commanded manually via the paddles. However, the can be the occasional hesitation upon downshifts.

This chassis is something of a masterpiece, with its combination of a 23mm wider track (over 3 Series) and 50:50 weight distribution resulting in a wonderfully predictable machine. The steering might be a little lacking in feedback – as is the case with the majority of electric steering systems today – but its is responsive and precise. The front-end grip and agile reaction to inputs creates a genuinely great car to throw around, even in sensible 420d form. An easy to modulate brake pedal enables keen drivers to accurately bleed off pressure as you round a corner with supreme confidence. Factor in the all-wheel drive all-weather security and you have a package that can justify itself as a true BMW, big grille or not.

Another big reason for buying a 420d is economy. Despite what the world’s governments are trying to persuade people, a modern diesel engine is still the most efficient way to cover long distances. This car claims a WLTP economy figure of 54 - 57mpg, which isn’t bad at all for a sporting coupe.

The new BMW 420d xDrive might split opinion when it comes to looks, but it is undeniable what an impressive machine it is to drive. Its fusion of comfort, strong performance, dynamics, economy and a coupe profile makes it something of a ‘have your cake and eat it’ type of car. A BMW 420d has always represented a real-world sweet spot for those longing for a coupe. This latest chapter of the 4 Series story only serves to bolster it as the de facto choice in this class.

An xDrive equipped 420d starts at £44,640 and considering the breadth of talents this car possesses, we’d say that isn’t bad value for money.

Facts and figures

Model tested: BMW 4 Series 420d xDrive M Sport

Price: £44,640

Engine: 2.0-litre turbocharged diesel + mild-hybrid

Transmission: 8-speed automatic

Power / Torque: 188bhp / 400Nm

0-62mph: 7.4 seconds

Top speed: 147mph

Seating: 4

Boot space: 440-litres

MPG: 54 - 57mpg

CO2: 135g/km

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