A new automatic gearbox from Mercedes-Benz will save fuel and cut CO2 emissions when it makes its debut on the E-Class.

It will make its debut on the 252bhp E350 Bluetec diesel from September production, where CO2 emissions will be reduced to 138g/km for the saloon model with fuel consumption of 53.3mpg.

The current E350 Bluetec with the 7G-tronic seven-speed automatic transmission, achieves 47.1mpg on the combined cycle.

In ninth gear at 75mph the engine runs at 1,350rpm, ensuring a quieter cabin environment as well as improved efficiency.

The gearbox, which is capable of handling up to 738lb-ft of torque, is expected to be rolled out over the next few years across other models in the Mercedes-Benz range currently using the 7G-tronic transmission.