BMW 4 Series Convertible review

Our Rating: 
2014 model
By Auto Express Test TeamComments

BMW 4 Series Convertible is a great cruiser that looks great and is reasonably efficient

Attractive styling, impressive engines, good to drive
Roof takes up a lot of space in the boot, compromised handling compared to coupe

The BMW 4 Series Convertible replaces the old 3 Series Convertible in the BMW range. The car uses the body and interior of the 4 Series Coupe, but swaps its fixed roof for a three-piece folding metal roof which tucks away neatly into the boot.

The BMW 4 Series Convertible attracts a £4,000-£6,000 premium over the coupe, depending on the model. It’s a rival to the Mercedes E-Class Cabriolet and Audi A5 Cabriolet, both of which have traditional fabric roofs.

Engines, performance and drive


As with the 4 Series Coupe, the 4 Series convertible sits 10mm lower to the road than a 3 Series saloon, this means it has the lowest centre of gravity of any model in the current BMW range. But while the Coupe version feels like a sports car the 4 Series Convertible feels more like a cruiser.

You can blame the added weight for that: not only does the complex folding roof its add weight but so does the extra chassis strengthening BMW has had to fit to the car to compensate for the loss in structural rigidity caused by effectively chopping off the roof.

In the case of the BMW 435i the Convertible is 295kg heavier than the Coupe. This is about the same as driving around with three international rugby players in the car with you at all times - that effects agility compared to the Coupe, which feels more like a sports car.

BMW 4 Series 435i Convertible tracking rear

That said the BMW 4 Series Convertible is still a slightly sharper drive than the Audi A5 Cabriolet and Mercedes. All models are rear wheel drive though the 435d xDrive has all-wheel-drive. The most economical model is the 420d. It’s 2.0-litre diesel is capable of 58.9mpg yet thanks to 181bhp has enough performance to satisfy most people.

Specifying an auto transmission adds £1,525 to the price and lowers emissions by 3g/km. It’s worth having because BMW manuals don’t have the slickest shift and the pedals are slightly off-set. Other options worth considering are the neck warmers, which blow hot air through vents in the front of the head restraint, and the adaptive suspension, as it improves comfort. Plus, at the press of a button you can put it in sports mode for a more dynamic drive.

MPG, CO2 and running costs


The 4 Series costs between £4,000-£6,000 more than the equivalent 4 Series Coupe to buy and the heavier weight means marginally worse performance and claimed fuel economy and CO2 figures.

Overall, the 420d makes the most sense. It may not sound as nice as the petrol models with the roof down, but this car is more set up for cruising around than being thrashed down a back road. What’s more emissions as low as 133g/km mean minimal tax bills for company car drivers.

Adding to the financial appeal – and making it easy for BMW owners to budget for maintenance – is a fixed-price servicing package, which provides five years or 50,000 miles of cover for around £500. The icing on the cake is excellent residual values.

Interior, design and technology


The BMW 4 Series Convertible is a fabulous looking machine roof up or down. Some cars with folding metal tops tend to have bulbous rear ends to accommodate the bulky roof mechanisms. But BMW has managed to engineer its way round this problem by using a three-piece design and complex folding mechanism.

BMW 4 Series 435i Convertible side

With the roof up the car looks very similar to the Coupe though and that means that it's longer, lower and wider than the 3 Series it replaces, and the rear wheel arches are the widest point of the car.

You can get the car in five trim levels: SE Luxury, Modern, Sport and thee range topping M Sport, which is marked out by more aggressive bumpers, side skirts and detailing and comes with the excellent adaptive dampers as standard.

Inside, the layout will be familiar to anyone who’s driven a 3 Series, with the same combination of an upmarket feel and a simple and smart layout. There’s slender buttons for the air-con and audio system, as well as the excellent central infotainment screen, while the 4 Series also benefits from BMW’s revised touchpad iDrive controller which alloys you to write letters into the satellite navigation using your finger.

As you’d expect, fit and finish are first rate, with quality materials used throughout while the low driving position enhances makes the car feel very sporty to sit in. Standard equipment includes Bluetooth, a DAB radio, cruise control and leather seats which are heated in the front – a welcome addition in a drop top.

There’s options galore such as the £1,990 Professional Media Pack and navigation. This may seem expensive but the huge screen has a fabulous display while the live traffic updates will help you avoid traffic jams.

Practicality, comfort and boot space


In the front, the 4-Series Convertible is just like the Coupe. So there’s plenty of adjustment in the drivers seat, a well laid out dash and large practical door bins. However, from then on there are compromises. The back seats are positioned more upright to make room for the roof mechanism.

BMW 4 Series 435i Convertible interior

This means they don’t feel so comfy over long distances and also affect the headroom – people over six foot will struggle in the back. Then there’s the boot. With the roof up it's 370 litres, which is pretty impressive, but if you take it down the space falls to just 220 litres which means you have to plan accordingly.   

Reliability and Safety


The BMW 4 Series uses many of the same mechanical and electronic components as the current 3 Series, so you can buy the coupe safe in the knowledge that it should be trouble-free. BMW offers a three-year unlimited mileage warranty and 36 months’ roadside assistance. BMW was the 10th-placed manufacturer in the Driver Power 2014 satisfaction survey, scoring well for handling and performance.

As you’d expect, you can pack your 4 Series Convertible with extra safety kit, including lane departure warning, a reversing camera, a head-up display and active cruise control.

Last updated: 19 May, 2014
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