GREG KABLE Published Date: 6/13/05
Mercedes-Benz seeks to reestablish its reputation as the world's finest luxury car builder with the launch of the new S-Class. Codenamed W221, the car is revealed here ahead of a planned world debut at the Frankfurt motor show in September.
Together with a bold exterior design, a heavily revamped interior and a range of powerful new gasoline engines, the sedan will trumpet several new safety features officials claim will make the S-Class the world's most advanced passenger car.
You don't have to look hard to recognize the new Mercedes flagship. Clothed in a larger and more upright body, the new S-Class looks more imposing than the car it replaces. Key styling cues include a reinterpretation of the classic Mercedes grille, large angular headlamps, a prominent line running along the sides, large wheel arches and a coupe-like rounded roofline.
Yet while the front is refreshingly sleek, the new S-Class tail bears an altogether different appearance, with a so-called separate fender treatment and free-standing trunklid similar to that adorning the BMW 7 Series. There is such disparity in the car's appearance front to rear, it is as though the two ends were styled by separate teams and joined in the middle.
The new S-Class is bigger in every dimension. Our unofficial tape measure reveals length extended by 1.5 inches, width by 0.35 inch and height by 1.1 inches. The car rides a wheelbase up by 2.75 inches over today's model, resulting in increases in interior accommodation and trunk capacity.
Complementing the new look will be a host of electronically controlled driving aids combining to make the W221 a technological tour de force-assuming everything works as advertised. These features include Brake Assist Plus, a system that automatically activates a brake booster when a series of low-frequency radar sensors mounted within the front-bumper assembly predict a critical braking situation is about to take place.
Using information from the sensors that monitor the road ahead, new software then determines the distance to cars ahead and both warns the driver via an LED readout when they are too close, and provides added braking power if it appears a collision is imminent.
In-house simulator tests found the accident rate was reduced from 44 percent to 11 percent with the new technology. Mercedes says it will eventually be made available to other carmakers after an undisclosed period of exclusivity. Statistically, every fifth car accident involves a front-to-rear-end impact, according to Mercedes. In its ultimate form Brake Assist Plus can brake the car automatically without the driver hitting the brakes.
In further developments Mercedes refined its Pre-Safe system. As well as pretensioning the seatbelts and return=ADing the passenger seat to its optimal position in critical situations, Pre-Safe automatically closes the side windows and inflates cushions in the front seats to optimize the effectiveness of the side airbag system.
The S-Class introduces night vision. Different from the thermal imaging process used by Cadillac on the STS, the optional system is based around a new infrared sensor that is claimed to identify objects more quickly and deliver sharper images.
Inside Mercedes plans to raise the already impressive safety credentials of the S-Class with a newly developed knee airbag, together with improved versions of today's front, side and curtain airbags that are said to react faster and be more adaptable, inflating to suit the size of the occupants with greater reliability.
The decision to focus on safety comes after concerns the S-Class, which pioneered such important technologies as ABS, airbags and ESP, was losing its reputation as a safety leader. "Nearly every car can achieve five stars in the Euro NCAP [crash] test these days," said a high-ranking insider, adding, "but Mercedes-Benz is the only carmaker to offer a fully integrated safety system."
Yet while the focus is on safety, the S-Class also promises added performance with the new four-valve-per-cylinder V6 and V8 engines. These supplant the three-valve-per-cylinder engines Mercedes thinks have reached the end of their development as far as future emissions regulations are concerned.
S350, with a 4.6-liter 330-hp V8 in the S450 and a 5.5-liter 388-hp V8 in the S550 likely. The 5.5-liter 500-hp twin-turbo V12 used in the current S600 will likely be brought over to the new model with little change. Later a 6.3-liter 504-hp naturally aspirated V8 will replace the 5.4-liter 476-hp supercharged V8 used in the S55 AMG. Topping the line will be an even more powerful version of the 6.0-liter twin-turbo V12 from the S65 AMG.
Mercedes makes no secret it is working toward introducing a hybrid version of the car. Speaking about the plans, Mercedes' head of development Thomas Weber said, "It will take less than five years and will be a typical Mercedes-Benz premium vehicle."
Two different hybrid drivelines are under development: a gasoline-electric system for markets such as the United States and Japan, as well as a diesel-electric system for Europe. The gas system uses Mercedes' 3.5-liter 272-hp V6 in combination with two electric motors, while the diesel variant is based around the new 3.0-liter
224-hp V6 common-rail turbodiesel.All engines will come mated to the 7G-Tronic seven-speed automatic transmission. The gearbox is reworked for the new model with the shift lever mounted on the steering column and operating by a new shift-by-wire arrangement, as on the 7 Series. The setup was first seen on the M-Class earlier this year and appeared on the R-Class, which uses the room freed up between the driver and front seat passenger for additional stowage space.
Standard models will again get rear-wheel drive, though Mercedes will push its four-wheel-drive system more aggressively with the new S-Class, extending its reach to a greater number of models and offering
4Matic in additional markets.After the problems and expensive recalls with the electrohydraulic Sensotronic Brake Control system, Mercedes retains traditional hydraulic stoppers for the new S-Class, which, like the CL, will be upgraded to simulate Sensotronic's many functions. Mated to the new brakes will be a more advanced electronic stability program and ABS, the latter reworked so the pulsating effect felt through the pedal under emergency stops is reduced.
Steel construction is retained, but more aluminum, including space-frame-style doors, ensures the new car's weight does not creep up too much on the 3825 pounds of today's S350. Holding true to tradition, there will be standard and long-wheelbase S-Classes from the outset of North American sales early next year.
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