BMW 320i xDrive

While a four-wheel-drive BMW that’s not an SUV is a bit of a novelty in the UK, customers on the Continent have been able to buy iX saloons and estates since the eighties.

The prohibitive cost of adapting the system to right-hand drive meant BMW had left Audi to scoop up sales of 4WD executive cars – but not any more. BMW feels the economies of scale have tipped in the buyer’s favour, and the latest 3 Series is its first car to be offered with four-wheel drive on the UK market.

Initially, the 320i’s 181bhp 2.0-litre turbo petrol will be the only engine available with the system. BMW admits that forthcoming diesel versions should prove more popular, but even without a hefty torque figure, the advantage of four-wheel drive is soon clear.

Just like the Audi A6 Allroad, the 3 Series xDrive has been designed primarily with on-road driving in mind. In normal use, power is split 40:60 between the front and rear axles.

A multi-plate wet clutch acts as a centre differential, which manages the transfer of power between the front and rear wheels.

In extreme conditions, it can shift up to 100 per cent of the available power to whichever set of tyres has more grip.

Unlike the Audi’s set-up, the BMW system is reactive – it relies on a set of sensors linked to the traction control system to detect when the wheels start to lose grip before it transfers the power to where it’s needed most. This results in a delay between the initial loss of traction and the system kicking in – but you’d be hard-pressed to notice the slightly slower response compared to the Audi’s set-up.

On a wet road, the benefits of this car over the rear-wheel-drive one are obvious. There’s a lot more front-end grip, and if you get on the power early out of a corner, there’s no hint of the oversteer that you come to expect from the standard model. Yet this extra grip hasn’t spoiled the BMW’s balance, while perfectly weighted controls and an eager engine mean the xDrive is as rewarding as any 3 Series. It looks almost identical, too: the only visual difference between this and a normal 320i is the slim xDrive badge on the bootlid.

Still, there are some penalties to pay. Most noticeably, the system adds a hefty 70kg to the car’s overall kerbweight. This has an impact on fuel economy, which falls to 41.5mpg, while CO2 emissions rise one tax bracket from 147g/km to 159g/km.

The £28,400 xDrive also costs a significant £1,535 more than the standard 320i, although it still undercuts the equivalent Audi A4 2.0 TFSI quattro by nearly £2,000.

Unlike the other cars in this test, the BMW has no off-road aspirations (it’s the lowest car here and has the least ground clearance), but it’s still a worthy addition to the range. Audi finally has strong competition when it comes to all-wheel-drive saloons, and we’re looking forward to trying diesel and Touring estate models fitted with xDrive.