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Models Covered

2dr Convertible (Petrol – 2.0 184hp [420i] & 252hp [430i], 6 cylinder 326hp [440i], 6 cylinder 431hp [M4] / Diesel – 2.0 190hp [420d], 3.0 6 cylinder 258hp [430d] or 313hp [435d] – trim levels SE, Sport, Luxury & M Sport)

Introduction

BMW’s first generation ‘F33’-series 4 Series Convertible persevered with the neat metal-folding roof that had been used by its direct 3 Series Convertible predecessor. This open-topped ‘4’ aimed to offer a different option to Executive segment cabriolet buyers not already swayed by the competing charms of rival open-topped versions of the Audi A5 and Mercedes E-Class. You won’t get the large boot and cutting-edge driving dynamics of the 4 Series Coupe, but compensations come in the form of refinement, security and drop-top desirability. You’d like one.

The History

It’s the thing that makes a BMW handle like a BMW should. We’re talking of the brand’s famous 50:50 weight distribution, something the Munich marque makes possible by the almost unique rear wheel drive configuration it applies to most of its models. But with this car, put at risk – the first generation ‘F33’-series 4 Series Convertible.

The reason for that is also the main reason why you might buy this car – its metal folding roof. Alone in the executive convertible segment in the 21st century’s second decade, BMW continued with this arrangement, rather than the soft-top fabric roof mechanisms rivals Audi and Mercedes used. It’s a unique touch that’ll tempt people liking the security, refinement and pavement wow factor of a folding metal top.

By 2014, with all Coupe and Convertible BMW models by then identified by even-numbered designations, that ‘3’ had become this longer, lower, wider ‘4’. Compared to the ‘E90’ model, this ‘F33’ design was more efficient yet more powerful, 40% stiffer and offered a 4WD option, along with extra hi-tech connectivity. Rear passengers got a little more space thanks to a wheelbase increase and luggage was a bit easier to get into the restricted boot.

The car was lightly facelifted and updated with various new petrol engines and suspension changes in 2017. And in that form, it sold until late-2020, when a second generation fabric-topped design arrived.

What You Get

In the 21st century’s second decade, BMW alone persisted with the metal-folding roof concept in the mid-sized convertible segment, so if you prefer this 4 Series Convertible to either of its two direct rivals, Cabriolet versions of the Audi A5 and Mercedes E-Class, that’s likely to be the major reason why. Having to create a pretty shape that effortlessly swallows all the roof-work’s sliding metal panels must have been quite a design challenge but here, that was reasonably well carried off, helped by the fact that like all the most modern folding hardtops, the BMW system - which takes 20 seconds to operate and can function at speeds of up to 8mph - uses three rather than two-pieces. The advantage of this is that you don’t need a distended rear end on the car to accommodate the larger sections of a two-piece roof. The downside of stacking three rather than two pieces on top of each other in the boot is that when they’re all folded and sandwiched together, there’s not a great deal of luggage space left. With the roof up, you’ll get 370-litres of cargo capacity. But fold it down and that figure falls to just 220-litres.

And at the wheel? Well, there’s a low-set driving position, a grippy three-spoke sports steering wheel and integrated retractable seatbelts handed to you by a neat ‘belt butler’ once you get in. Otherwise, the cabin’s typical BMW from this period.

What To Look For

Obviously the roof is the first thing to check. Check that it opens and closes in around 20 seconds and there are no undue whistles and creaks when it’s in place. Various recalls when the car was new concerned issues with engine stalling and the bolts on the rear axle. Check that these recalls have been attended to if they apply to the car you’re looking at. Most of the 4 Series Gran Coupe buyers in our ownership survey were very happy with their cars but inevitably, there were a few that had issues. One owner mentioned corroding brake calipers and a disfiguring of the trim panel over which the folding roof sits. Check both issues. Otherwise, it’s the usual issues; check for kerbed alloys and insist on a fully stamped-up service history.

On The Road

Over 60% of original buyers favoured a black pump BMW, so you’re very likely to find a 420d variant, a car with the same 184 braked horses as its petrol-fuelled 420i counterpart but nearly 30% more torque, 380Nm making itself keenly felt from low revs. Diesel drivers in search of extra horsepower can get the 425d variant. A six cylinder diesel in this car though, takes performance to another level. The 430d manages 0-62mph in 5.9s, while the top automatic-only 435d reduces that to 5.2s and adds the standard security of xDrive 4WD.

For models made in the 2014-2017 period, the first of the petrol variants was the 245bhp four cylinder 428i, good for 62mph in 6.4s, which makes it only fractionally slower than the six cylinder 306bhp 435i – and at a substantial saving. If we couldn’t stretch to the flagship 431bhp six cylinder twin turbo supercar-slaying M4 model, then we think the 428 would be our variant of choice.

But we haven’t yet talked about the roof. It’s nice that you don’t have to stop at the side of the road to either retract or erect it, though you do have to slow to a speed of below 8mph for the 20 seconds the three metal panels take to assume their necessary positions. When the top is up, the refinement you get is indistinguishable from that you’d expect to find in the 4 Series Coupe model, thanks to a number of design improvements made to this Convertible version. These include a sound-absorbing headliner that reduces wind noise by up to 2dB.

This 4 Series Convertible was updated in 2017 and as part of the changes, the 428i and 435i petrol variants were, respectively, replaced by 430i (252hp) and 440i (326hp) models, which sat below the range-topping 431hp M4 variant.

Overall

A lot of boxes are ticked by this car if you can afford its asking price. You get impressive safety systems, high residual values, above average rear seat legroom and a sheer depth of engineering that rarely fails to impress. As a result, in many ways, it’s probably the most complete contender in this segment from this era and, best of all, it looks as striking and expensive as a convertible of this kind should when the sun’s out and all is right with the world.