Mercedes-Benz debuts new nine-speed automatic transmission

The first nine-speed automatic transmission with torque converter, the 9G-TRONIC for premium vehicles, is celebrating its world premiere in the E350 BlueTEC, which is set to become one of the most fuel-efficient six-cylinder diesel models in its class.

Thanks to the high level of efficiency of the patented transmission design, the 252bhp V6 diesel engine in the E350 BlueTEC, which is available as Saloon and Estate models, has an average NEDC fuel consumption of 18.9km/L (Estate: 18.2km/L), corresponding to CO₂ emissions of 138g/km (Estate: 144g/km). As a result, the new models with 9G-TRONIC undercut their predecessors in terms of both consumption and CO₂ emissions.

As part of this, the broad ratio spread of 9.15 for gears one to nine enables a clearly perceptible reduction in engine speed and is a decisive factor behind the high level of energy efficiency and ride comfort. Shortened shift and reaction times ensure optimum spontaneity combined with outstanding ease of shifting. In manual mode and the S programme in particular, the 9G-TRONIC responds significantly more spontaneously and enhances driving pleasure.

In the case of the nine-speed automatic transmission, the development engineers also focused on the area of "compact lightweight construction". Despite two additional gears and a maximum transferable torque of up to 1000Nm, the new automatic transmission requires as little installation space as its predecessor and is lighter. The two-piece housing design has also been retained, with the torque converter housing made of lightweight aluminium, while the transmission housing with weight-optimised plastic oil pan is made of an even lighter magnesium alloy.

The 9G-TRONIC is suitable for rear-wheel and all-wheel drives as well as hybrid and plug-in hybrid drive systems and will be used in almost all model series and engines in the coming years.