Compared to the previous model series, the Mercedes engineers have further enlarged the deformation zones substantially in the front and rear sections of the new CLS, as well as improving the energy flows. The front crumple zone has four independently acting impact levels, meaning that the forces can be distributed over a wide area while bypassing the passenger cell.

Sectional panelsabove the wheel arches form the upper side-member level. From here, the impact forces are channelled into the A-pillars and, subsequently, into the roof frame.
An aluminium crossmember connects the forward-extended side members and ensures that the forces are transferred to the side facing away from the impact. The crossmember and the forward-extended side members form the central impact zone.
The subframe to which the engine, steering and front axle are attached also serves as an impact level in the event of a frontal collision. It is made of high-strength steel and, depending on the engine variant, can be connected to the newly developed floor side members by means of special supporting tubes. As a consequence, the subframe can deform in a predetermined manner and absorb energy in the event of a crash on the one hand and channel high impact forces straight into the vehicle floor on the other.
The side skirts have been extended forwards to support the wheel and prevent it from entering the footwell in the event of an offset frontal collision. In order to provide specifically targeted front-wheel support and location, Mercedes-Benz has also developed special struts and additional energy-absorbing elements for the wheel arches. The struts are arranged diagonally and prevent the passenger cell from sinking in the event of an impact.

The firewall is a four-part construction. This design enables Mercedes engineers to vary the material thickness according to the level of vulnerability in an accident. As the load acting on the firewall during a frontal crash is greatest in the lower section, the sheet steel used here is almost 50 percent thicker.

As well as being a major reason behind the high level of impact resistance, this intelligently designed bodyshell not only enhances ride comfort, it also reduces noise and vibration. The Sindelfingen engineers paid particular attention to the connecting points between the suspension and the bodyshell, which are required to withstand very high forces. These were specifically reinforced to ensure that road-induced vibrations are not transferred to the body at the expense of driving enjoyment. An indicator of the excellent overall result is the static flexural strength of the bodyshell, which shows a 28 percent improvement over its predecessor. Torsional strength increased by six percent.