You've got to hand it to BMW. After the spectacularly dissolute
X5 M and X6 M partnership, we now get this: the xDrive 18d, a 4x4 about as green as they come without resorting to pedal power.
It follows BMW's penchant for long-winded names for its SAVs (sports activity vehicles), with the '18' bit signifying how clean the 2.0-litre diesel engine is, rather than representing a 1.8-litre oil burner. So, here's how clean it is: 45.6mpg, 165g/km (VED band D, £145) and EU5 emissions standard, which means that all the other pollutants diesels spit out that we tend to forget about - because they don't affect how much tax we pay - are kept in check too. Great.
All that makes it the cleanest small premium 4x4 money can buy, and yet it still performs ok too. It's got 258lb.ft of torque at 1,750rpm and 141bhp, so the dash to 62mph takes 10.3 seconds and it tops out at 121mph. What it doesn't do, however, is make the X3 fundamentally any better. Still, if it's clean you want, you can order one now. Don't ask us how much, because BMW isn't saying yet, but circa £28k doesn't seem unreasonable.
Mark Nichol - 16 Apr 2009