BMW 120d xDrive

It's a BMW 1-series with four-wheel drive. UK orders for the BMW 320i xDrive since its book opened in June have been encouraging, and have had us eyeing Munich’s other non-SUV four-wheel-drivers with interest. In Germany, most models can be had with xDrive, including the 1-series hatch in sprinting M135i form and in workaday 120d guise as seen here.

The model answered demand from Germany, Austria and Switzerland, and joins an expanding xDrive range that already accounts for a third of BMW's sales. Germany, the USA and China all buy more xDrives than Audi quattros, so, clearly, that leaves room for improvement in the UK.

Most of Audi's quattro-equipped cars use a Torsen centre differential to apportion torque but, like the A3 and TT, xDrives use a multi-plate wet clutch instead. BMW claims its system is the most quick-witted, reacting in 0.1sec, and anticipating wheel slip via the DSC’s myriad sensors. Torque can be totally redistributed fore or aft from the default 40 per cent front, 60 per cent rear setting.

The 120d xDrive is largely identical to its rear-drive counterpart that was packaged to accommodate four-wheel drive from the start. The extra 40kg or so, plus friction increases, means a 4g/km CO2 penalty (theoretically adding £70 to the road tax bill on the smallest wheels), while fuel economy drops less than four per cent to a still-superb 60.1mpg, and performance is barely affected. BMW chassis engineers have aimed to maintain the rear-driver’s sporty-yet-supple set-up using revised springs and dampers.

The sensible money banks on both winter tyres and four-wheel drive, and that’s how our test car was equipped for a stint in the Austrian Alps. On snow, the xDrive system was hamstrung by DSC, which constantly cut the power, but switch the Dynamic Traction Control to a setting that permits some slip and understeer could be tamed with an increase in rear-bound drive without stifling progress.

Similarly, on the driest road we found, the 120d xDrive showed signs of overcoming the rear-driver’s strong tendency to wash out. Unless DSC was fully engaged, though, unchecked oversteer would cut doughnuts in the snow all day. When required, the ABS system performed efficiently and inspired confidence, while the accurate steering was uncorrupted by xDrive.