Mercedes M-Class• Capable of 47mpg
• On sale in spring 2012
• Class-leading aerodynamics

The third generation Mercedes M-Class will achieve ‘class-leading economy’ for a big 4×4 according to the German company’s engineers and goes on sale in spring 2012.

Most thrifty is the four-cylinder ML 250 BlueTEC 4MATIC, which delivers an average fuel consumption of 47mpg and emissions of 158g/km, despite having 204bhp and 369lb/ft of pulling power. Fitted with the optional 93-litre fuel tank, this gives it a range of 930 miles.

The most economical BMW X5 manages 38.2mpg and 195g/km with 245bhp, while the Land Rover Range Rover TDV8 averages 30mpg and emits 253g/km of CO2.

At launch there will also be a 350 BlueTEC 4MATIC model with 258bhp, managing 41.5mpg, and a petrol 350 4MATIC BlueEFFICIENCY with 306bhp capable of 33.2mpg that has a top speed of 146mph.

Two of the biggest improvements in economy have come from engine downsizing and class-leading aerodynamics. Friction inside the engine has been reduced using a technology developed by AMG for performance models including the C-Class Coupe C 63 AMG.

The nose features a huge grille and long bonnet with aggressive air-intakes at the base of the windscreen.

Inside, an enhanced COMAND system has a large high-resolution screen sitting in the central console and offers internet access and apps for Google Local Search plus access to Facebook and even weather information.

By Andy Goodwin, senior web journalist