ECHOING the X3 SUV range, BMW Australia has added a new entry-level diesel model to the 5 Series saloon line-up.

Not only is the new 520d the cheapest 5 Series available at $79,900 – coming in $5000 below the similarly-equipped 523i – but it is some $35,000 less than the only diesel model previously available, the six-cylinder 530d.

Although BMW diesel sales have stabilised in 2007 at about the same rate as 2006 – which was double the previous couple of years – sales of the 530d have dropped to about half what they were last year when the model was fresh, so the company will be expecting the 520d to make up lost ground.

Sharing its all-alloy turbo-diesel engine with the 120d and 320d as well as the new X3 2.0d, the new entry-level 5 Series produces 125kW of power at 4000rpm and 340Nm of torque from 1750 to 4000rpm.

With a standard six-speed Steptronic automatic transmission, the 520d accelerates from rest to 100km/h in 8.6 seconds – 1.5 seconds slower than the bigger-engined 530d.

However, it uses only 6.1 litres of fuel per 100km compared with the 530d’s official figure of 7.5L/100km.

Compared with the 140kW/230Nm 2.5-litre petrol-engined 523i, the 520d not only costs $5000 less, but it accelerates to 100km/h half a second faster, uses only two-thirds of the fuel and produces about 10 per cent fewer CO2 emissions.

Apart from the engine, the only difference between the two models is the lack of active steering on the 520d, otherwise the features and specifications are the same.

That means standard stability control, ABS brakes, eight airbags, 16-inch star spoke alloy wheels (without run-flat tyres), high-gloss wood interior trim, Dakota leather upholstery, a 6.5-inch colour control display monitor, Bluetooth phone preparation, in-dash CD player and CD changer in the glovebox, USB audio interface, dual automatic climate control, automatic interior mirror, multi-function leather steering wheel, on-board iDrive computer with outside temperature display and power adjustment for front-seat backrest angle and height.

At the same time as introducing the new 520d, BMW Australia has also introduced two new technologies to the 5 Series range – variable light distribution and crash-activated headrests.

Variable light distribution will be optional on 5 Series, but the crash-activated headrests, which are a development of the existing active head restraints, are now standard on all 6 Series, 5 Series, X5 and X3 models.

In the event of a rear-end impact, the pyro-activated headrests almost instantly move forward by up to 60mm and upwards by up to 40mm to reduce the gap to the occupant’s head and therefore reduce the effect of whiplash.

Variable light distribution technology varies the shape of the illumination cast by the headlamps according to driving conditions.

Having made adaptive headlights (which turn with the steering) standard with the introduction of the E60 5 Series in 2003, followed by optional automatic high beam dipping in 2005, this is BMW’s latest development in enhanced lighting.

Dependent on road speed, the variable light distribution system automatically enlarges the driver’s field of visibility by broadening the light beam, or the “footprint” of light.

In a typical city night-time driving situation at speeds below 50 km/h, the system ensures a broader distribution of light making it easier to recognise objects on the oncoming side of the road.

The foglights activate automatically at speeds of up to 70km/h to generate a broader light distribution and brighten up the area close to the car.

At higher speeds, the field of vision is extended by giving the light beam a longer range, and offering greater illumination on the far side of the road.