A prototype of the Mercedes-Benz E-Class (W213) has been photographed while undergoing preliminary testing.

A prototype of the Mercedes-Benz E-Class (W213) has been photographed while undergoing preliminary testing.

The all-new E-Class is bound to grow in size to better distance itself from the C-Class and despite the increased dimensions it will lose some serious weight as a result of switching to the MRA platform also used by its smaller sibling. Some of the added size will be noticeable in the wheelbase which means there's going to be a more spacious interior cabin with additional legroom for rear passengers.

These are the best spy shots yet of the new E-Class (W213 generation) and although the prototype is wearing a significant amount of camouflage it's easy to notice the design will be influenced by its C- and S-Class brothers.

One of the main novelties the overhauled E-Class will bring is going to be represented by a new family of straight-six gasoline engines which will have displacements ranging from 2.2 to 3.5 liters. Also on the menu could be a 2.9-liter turbodiesel rated at 313 HP (230 kW) and 400 HP (294 kW), as well as hybrid and/or plug-in hybrid setups mixing up 2.0-liter gasoline or diesel engines with an electric motor rumored to develop about 122 HP (90 kW).

The engine lineup will once again be topped by an AMG variant that will likely be equipped with the recently introduced V8 4.0-liter twin-turbo found in the AMG GT and C63 AMG. Some of the engines will probably be offered with a nine-speed automatic gearbox already available on the current generation E350 BlueTEC.

Aside from the standard sedan, it is believed Mercedes-Benz will offer the new E-Class as a long wheelbase sedan, coupe, estate and convertible. The fixed roof derivatives are likely to become sportier whereas the open-top versions are believed to be more luxurious.

According to a report published earlier this year, the Mercedes-Benz E-Class W213 is scheduled to go on sale at home in Germany in March 2016 which could mean an online reveal will occur before the end of next year.

Gallery: Next generation Mercedes-Benz E-Class spied testing and carrying production body

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