For the first time in 60 years since the history of the flagship Mercedes-Benz S-Class, it will be available with a 4-cylinder engine. The first ever 4-cylinder S-Class model will be the Mercedes-Benz S250 CDI, using their new 2.2 litre twin-turbocharged diesel engine making 204 horsepower and 500Nm of torque. That’s probably more than enough torque to move the large luxo-barge around – it’s definitely more than the petrol-powered baseline S300 that’s sold here in Malaysia.

There are currently no Mercedes-Benz diesels officially on sale in Malaysia, and I think the new “250 CDI” engine is officially incompatible with our Euro 2M diesel fuel, since the C250 CDI test unit that was available only to selected media to drive earlier in the year used fuel that was specially imported from overseas.

The S250 CDI will also get auto stop-start technology, and combined with the turbodiesel engine it is rated to achieve a combined fuel consumption of 5.7 litres per 100km and output CO2 of 149g/km, which Mercedes-Benz claims is the first vehicle in its class to be able to hit CO2 emissions of lower than 150g/km. 0 to 100km/h is reached in 8.2 seconds.

And what are the company’s rivals doing? BMW CEO Norbert Reithofer said there are no plans at the moment for a 4-cylinder 7-Series, even saying at last month’s Paris 2010 show that he likes selling 7-Series with 6 and 8 cylinder engines. BMW plans to offer “electrification” of the existing 6 cylinder and 8 cylinder engines instead, which probably means some kind of hybrid solution.

Audi does have a 4-cylinder A8 in the plans but it involves a gasoline engine (probably Volkswagen Group’s widely used 2.0 TSI engine) instead of Mercedes-Benz’s turbodiesel approach.