Among the changes is the addition of urea injection to the exhaust system of the E220 Bluetec and E250 Bluetec.
Fuel economy is improved from 61.4mpg to 64.2mpg in the E220 Bluetec saloon and from 47.9mpg to 53.3mpg in the E350 Bluetec saloon, with both featuring EU6 emission compliance.
Economy is also improved on the E300 Bluetec Hybrid, from 68.9mpg to 74.3mpg in saloon guise.
Further up the line-up, the E350 Bluetec receives a revised 3.0-litre V6 diesel engine boasting an added 6bhp at 254bhp along with an updated version of Mercedes-Benz’s newly introduced nine-speed automatic gearbox.
On the petrol side, the E400’s turbocharged 3.0-litre V6 engine has been replaced by the larger 3.5-litre V6 recently unveiled on the CLS400. Power and torque remain the same at 328bhp and 354lb ft, with the E400 coupé returning 40.9mpg.
Emissions gains mean that CO2 figures have dropped across the board, lead by the E300 Bluetec Hybrid, which emits just 107g/km.
The changes also mean the E350 Bluetec now reaches 0-62mph fractionally quicker than the current car, at 6.4 seconds (down from 6.6 seconds), whicle the E350 Bluetec Hybrid completes the same sprint in 7.1 seconds, down from 7.5 seconds.
Standard equipment on the E-class has also been bolstered by the addition of the Collision Prevention Assist Plus system.
The technology, which helps to reduce the impact of rear-end accidents via visual and auditory warnings as well as partial autonomous braking, will be fitted as standard to all E-class models.
New Premium and Premium Plus packages also add further luxuries to the E-class. The Premium package includes a panoramic glass sunroof, a memory pack, rear split folding seats and a reversing camera on saloon models for £2695. Premium Plus adds keyless go and an upgraded sound system for £3895. On estate models, prices for those packages is £2395 and £3495 respectively.
Price increases across the range now means that the entry-level E220 Bluetec saloon in SE specification starts from £34,270, compared to £32,750 for the older E220 CDI. Similarly, the E-class estate now starts at £36,060.
The upgraded E-class models will be available from September.