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The new Mercedes E-Class—and its forerunners.

About 10% of the body-in-white is made with aluminum.

E-Class: Time for a Change

Over the last 10 years or so, the Mercedes-Benz model range has transformed from being something that was generally worthy but really rather dull into one that sparkles with aspirational models in all segments–with perhaps one exception.

Over the last 10 years or so, the Mercedes-Benz model range has transformed from being something that was generally worthy but really rather dull into one that sparkles with aspirational models in all segments–with perhaps one exception. The E-Class has long been the car that time forgot. While the Stuttgart automaker was bringing out the SLK, CLK coupe and cabriolet, the M-Class, the Smart and A-Class in Europe, and revitalising the S and C-Class cars as well as the SL, the poor old E-Class languished in the shadows. Unless you were a Frankfurt cab driver, you really did not aspire to have it sitting in your drive–even though, it has to be said, almost 11 million of them have been sold in various guises over the years, including around 1.4 million of the current version since 1995. Now, though, its time has come.

Rather surprisingly unveiled at the Brussels Show, a relatively low-key national event just one week after the hubbub of Detroit, Jürgen Hubbert, the DaimlerChrysler main board member responsible for all Mercedes-Benz passengers cars and Smart, introduced the latest version. Against a backdrop of video images of ocean-going yachts ploughing their way through high waves and over-loud music reverberating around the hall, the new E-Class was greeted as “the guiding star in its segment” that has “been showing the competition the way for more than five decades.”

True or otherwise, the latest version is unquestionably a step forward on the outgoing model in all aspects, showcasing a number of innovative features. While the distinctive twin headlamp arrangement remains, albeit a little modified to bring it more into line with the current Mercedes look, the real interest lies below the surface–specifically, the suspension and brakes and under the hood.

Smart Suspension. First seen on the S-Class at the end of 1998, the air suspension system has been further refined on the new E-Class so that both the springs and shock absorbers are electronically controlled. Called “Airmatic DC”–for Dual Control–it is able to enhance ride and cornering stability without sacrificing comfort. With the shock absorbers and springs regulated by compressed air, the suspension can be minutely tuned to all road surfaces and the car’s speed. At the same time, the driver is able to select one of four suspension settings ranging from the relative harsh sporting one to the more floating comfort option. Other features include all-round self-levelling suspension and the body being lowered by 15 mm at both axles at speeds in excess of 140 km/h (87 mph). On rough, potholed roads the body can also be raised by 25 mm up to speeds of 120 km/h (75 mph). The Airmatic control unit receives its signals from two sensors in the front and rear axles that monitor the level of the body, three acceleration sensors mounted on the body and a steering angle sensor. Airmatic DC is standard equipment on the new E 500 V8 model and as an option on the rest of the range.

As far as the suspension hardware is concerned, the double wishbone front axle has been replaced with a four-link system that not only improves wheel location, steering precision and comfort, but also has better deformation characteristics in head-on collisions. The basic multi-link rear axle design is carried over from the outgoing model.

 

Brake-by-Wire.

The braking system, though, is not. While the electrohydraulic Sensotronic Brake Control (SBC) is a known factor and is fitted on the new SL, it is the first time that such “by-wire” brake technology is to be found on such a mass-produced vehicle. Four wheel-pressure modulators meter the brake pressure according to requirements and pass it on to the brakes via the control unit that takes into account such things as the speed of the wheels, the steering angle, and lateral acceleration, while also communicating with the engine and transmission control units. Four pressure sensors in the wheel pressure modulators and one pressure sensor each for the hydraulic accumulator and for the brake commands monitor the processes. The vacuum brake booster has become redundant, while the brake pedal and master brake cylinder become a single operating mechanism that is hydraulically uncoupled from the rest of the system by valves, and serves only to record the brake request.

 

Modern Materials.

The bodyshell itself is the stiffest in the segment, claims Mercedes-Benz, and yet at just 437 kg (963 lb.) the new model is no heavier than the previous one. “This involved us almost doubling the percentage of high-strength, high-tech steel alloys used to nearly 40% by weight,” said Helmut Petri, member of the Divisional Board for Mercedes-Benz Passenger Cars and Smart, head of production.

High-strength steels account for 37% of the bodyshell’s weight, an increase of 17% over the previous model and include what Mercedes describes as “cutting edge” dual-phase steel–which is capable of withstanding extremely high loads–that is used for various underfloor components. Aluminum accounts for 10% of the bodyshell weight in the new E-Class, which is a higher proportion than in any other previous large-scale production Mercedes. The hood, front wings, trunk lid, front and rear-end module carriers, the rear-end module, the parcel shelf, and the rear wall behind the rear seat backrest are all made of aluminum.

 

Improved Diesels.

While of less interest in the U.S. than Europe, the new E-Class also features the next-generation common-rail diesel engines. With compression ignition cars now accounting for around 40% of new car sales in Europe, it is vitally important for all automakers to ensure that they have the latest diesel technology in their latest models. In this case, it is a development of the four-cylinder 220 CDI and five-cylinder 270 CDI units that first appeared in 1997. A new high-pressure pump, seven-hole injector nozzle which replaces the previously used six-hole nozzle, and an increased injection pressure from the previous level of 1350 bar to 1600 bar have all played a significant part in reducing fuel consumption. However, it has been the adoption of counter-balancer shafts that has significantly reduced vibrational input and enhanced overall refinement in the E 220 CDI. The range will be further expanded with two more diesel engines during the course of the year.

As far as gasoline engines are con-cerned, there are the 2.6- and 3.2-liter V6’s and the top-of-the-range 5-liter V8 from the S-Class, all of which have undergone some modification but which remain essentially the same. Later in the year, a performance-derived AMG version with a new engine will also be launched.

While the E-Class will never be one of the sexiest of Mercedes models, the new version is quite a substantial improvement on the outgoing one. “The new E-Class represents the pinnacle of what is now possible in the field of emotive and technical intelligence in its segment,” said Professor Hubbert at the launch. It has cost the company $700-million on development and $1-billion on production, relatively modest amounts by industry standards on a car that is destined to become one of its staple diets. Whether the Frankfurt cab driver will really appreciate the investment, though, remains to be seen.