The facelifted S-Class will be the first model to carry the new inline six petrol engine which will come with 48V mild hybrid tech next year.
The new powertrain will come with an electric motor attached to the crankshaft, acting as both an alternator and a starter.
Codenamed M256, the new engine is the second member of Mercedes’ new family of engines and is closely related to the OM654 four-cylinder diesel that debuted in the E-Class. Mercedes is keen to replace almost all existing petrol V6s in their range with the M256, according to C&D’s report.
The company didn’t release any specs of the new powertrain apart from saying that the electric motor will be able to boost the engine’s performance by up to 18hp and harvest up to 20hp of regenerative braking.
Being bolted on the crankshaft will allow it to start the engine in a fraction of a second but it will not be able to move the car on electric power alone. Mercedes also says that the system will assist when the gasoline engine is running at less than 2000rpm.
Despite the small power gains and the narrow window of operation, the company promises an economy improvement of 10 to 15 per cent. The new 48V system is also going to replace all of Mercedes’ non plug-in hybrid models with a longitudinally mounted powertrain.