THE ODO ON our X5 has just rolled past the 11000km mark, 6 500km of those completed within our care. It’s been interesting to watch the fuel consumption improve from month to month as the big Bavarian gets more miles under its belt.
The first month we averaged 11.1ℓ/100km, the next 10.9, while the next saw an increase to 11.4ℓ/100km average due to our ski boat towing ventures. This month it was back down to 10.2ℓ/100km. These are all still some way off BMW’s claimed average fuel consumption of 7.5ℓ/100 km (in the EU test cycle).
But the big three-litre straight six hasn’t missed a beat (touch wood!) since it arrived in our fleet. The engine is part of a new generation of lightweight, all-aluminium BMW power units featuring common-rail direct injection, piezo injectors which operate at a maximum pressure of 2 000 bar, and a single turbocharger. The same TwinPower turbo technology was first employed in the BMW 740d luxury saloon, and our 40d unit delivers 225kW and maximum torque of 600Nm available between 1 500 and 2 500rpm. As much as 450Nm is available from a low 1 000rpm, which is great for towing, off-roading or blitzing GTIs at the traffic lights. BMW call the technology the ‘Variable Twin Turbo’, and what it means is that from just above idling speed, a small charger is activated, with an additional larger charger coming into play at higher revs when more torque is required.
Allied to this grunty diesel, our test unit is equipped as standard with BMW’s new ZF-sourced eight-speed automatic transmission. Apart from offering rapid, almost undectable (and mostly intuitive) shifts between cogs, BMW claims the extra ratios help cut the fuel bills compared to the previous X5’s six-speeder. Our experience so far backs this up.
UPS | Fuel consumption continues to improve with mileage
DOWNS | Seeing a matte black poser from the X5 club, see pic above