Nobody was more surprised than Mercedes when its diesel-powered S320 CDi became the range's best-seller. Nobody other than BMW that is! But now it's joined the club with its new 730d.
The UK will only get the 3.0-litre six-cylinder although Europe has the option of an even more potent 4.0-litre V8, but we needn't worry. The latest turbo six has lost weight, and updated common-rail injection technology gives extra power, improved economy and refinement that would shame many a petrol-engined rival. You'd never know it was a diesel, even starting from cold - it's smooth and incredibly punchy. We're talking 218bhp and 500Nm of torque, giving 146mph and 0-60mph in eight seconds. All this comes with 33.2mpg economy - and tax benefits.Throw in world firsts such as the only turbodiesel with a six-speed automatic
Better than that, it can hit 100mph in just 17.7 seconds, thanks to that entirely healthy 242bhp and 398lb ft. To put that into sprinting limo perspective, that’s as fast as any hot hatch you care to mention. Now take into account 192g/km and the fact that on test, I averaged 43mpg, and you have a strong case for not bothering with any other engine. You might get to places faster, but you’ll have to stop – and that’s without taking into account the fact that you’re unlikely to be able to reasonably deploy any of that extra power in the UK without being put in prison with paedophiles.
