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Page 1 : Mercedes S550 Page 2 : PRE-SAFE brake Page 3 : Engine Page 3 : Automatic transmission Page 3 : Safety Page 3 : Options Page 3 : Packages Page 3 : Prices EngineThe Italian autostrada moves quickly, but heavy traffic has us slowing repeatedly. The new V-8 engine, now with four valves per cylinder and displacing 5.5 liters, is turbine smooth and virtually silent, only finding its voice at the upper reaches of the rev range. The S550 gathers speed quickly, more quickly than before, but doesn’t rocket forward with a vengeance (for that you need the twin-turbocharged V-12, which, according to the factory, sends the S600 from 0 to 62 mph in a supercar-like 4.6 seconds). The frequent braking gives us ample opportunity to appreciate the good, old-fashioned, mechanically applied hydraulic brakes, which are much easier to modulate than the much-maligned and trouble-prone SBC brake-by-wire system in the E-class. That system was originally planned for the S-class as well, but Mercedes is now phasing it out. In testing, the 5.5-liter V8 with 382 horsepower and 391 pound-feet of torque propelled the 4,270-pound S550 to 60 mph in 6.1 seconds. The quarter-mile flew by in 14.2 seconds with a trap speed of 101 mph. The quickest runs were accomplished by letting the engine and seven-speed transmission do all the work. Manually shifting by means of the steering-wheel-mounted shift buttons actually produced slower times, an indication that the shift algorithms have been massaged as much for speed as smoothness. In real-world driving on flat terrain, the engine is barely ticking over at 2,000 rpm at 80 mph, thanks to a combination of the 0.73-to-1 top gear and 2.65-to-1 final drive ratio. Engine 5,461-cc DOHC 32-valve V-8. Die-cast aluminum alloy cylinder block. Aluminum alloy heads. Fuel and ignition system Sequential fuel injection and twin-spark ignition. Four valves per cylinder with continuously variable intake and exhaust valve timing. Fuel Tank Capacity 23.8 gal/90 liters - 2.9 gal/11 liters. Transmission Steering wheel mounted shift buttons allow for Touch Shift gear selection. Electronically controlled shifting. Driver-adaptive programming adjusts shift points to the driver’s current driving style. Driver-selectable Comfort mode starts vehicle moving in 2nd gear, or a 2nd Reverse gear, and upshifts at lower rpm to help improve control on slippery surfaces. Drive configuration Standard rear-wheel drive. In the new eight-cylinder engine the engineers at Mercedes-Benz have optimised the effect of this four-fold, continuous camshaft adjustment by using what are known as shifting camshafts. These control the opening of the exhaust valves and improve the engine’s gas cycle even further. Depending on the ignition sequence, the exhaust cams are designed in such a way that the valves open at different ti-mes during the exhaust cycle. This reduces the pressure fluctuations in the ex-haust tract which are inherent to a V8 engine, and which lead to fluctuations in the residual gas content in the cylinders. With a specific fuel consumption of 233 grams per Kilowatt hour (g/kWh) when operating at peak efficiency, and 345 g/kWh at part-throttle (2000 rpm, 2 bar), the engine has easily the lowest fuel consumption in this displacement and output class. ---- Automatic transmissionThe new S550 saloons is specified as standard with the 7G-TRONIC seven-speed automatic transmission, the only passenger car transmission of this type in the world. 7G-TRONIC incorporates numerous engineering innovations which, in conjunction with the state-of-the-art engines, provide enhanced accel-eration and mid-range power, reduced fuel consumption and greater shifting com-fort. 7G-TRONIC is combined with the DIRECT SELECT gearshift, which replaces the conventional centre console-mounted automatic selector lever. A brief press of the DIRECT SELECT steering-column selector lever allows the driver to select the "P", "N", "R" and "D" positions. The commands are transmitted electronically, although the actual gear changes are actuated by cable.The S/C/M/ mode selector switch on the centre console allows the driver to choose between three different modes: Sport, Comfort and Manual. As well as the transmission characteristics, these modes also allow the characteristics of the ac-celerator pedal and the suspension (springing and damping) settings to be varied. In Manual mode, the driver changes gear using the steering-wheel gearshift buttons. The special characteristics of the seven-speed automatic transmission are attrib-utable to various different design features, the most important of which is the in-crease in the number of forward speeds from five to seven. This results in a wider overall ratio spread, while at the same time the ratios are also closer together than on the five-speed transmission. An optimal ratio can therefore be selected for vir-tually all driving situations. The fact that the electronic control unit has a greater number of ratios to choose from also reduces fuel consumption and increases smoothness. Depending on driving situation, average engine speeds at 100 km/h are approximately twelve percent lower than with a five-speed automatic trans-mission. The optimal matching of engine speed to driving conditions means that the engine is more economical on fuel and is also quieter in operation. The Mercedes engineers have also made important advances in terms of the transmission’s control logic: if the 7G-TRONIC transmission needs to shift down quickly through several gears, for example under kickdown, a multiple downshift function comes into operation. Instead of changing gear sequentially, one gear at a time, the transmission shifts down by up to four gears at a time, depending on the driving situation, resulting in significantly faster shift times. The new seven-speed automatic transmission is fitted with a hydrodynamic torque converter with lockup clutch. Whenever possible, the lockup clutch creates a virtually rigid connection between the engine and the transmission shaft, thus preventing slip between the pump and turbine, and thus power losses, in a wide range of operating situations. On the Mercedes-Benz seven-speed automatic transmission, the lockup clutch engages even in first gear, rather than only in the higher gears as on conventional automatic transmissions. On comfort grounds, the torque converter lock-up clutch is slip-controlled and therefore engages very smoothly.
SafetySafety, comfort, dynamics and longevity - these and other outstanding features of the new S550 are based to an important degree on its body shell. It acts as a sturdy backbone that reinforces the chassis, ensures precise handling and prevents uncomfortable vibrations. It also fulfils the most stringent Mercedes safety guidelines and features an intelligent lightweight design, exemplary aerodynamics and noticeable improvements in the area of acoustics. The high design quality of the new flagship Mercedes model likewise owes a great deal to the body technology - with its carefully formed panels, precise joins and exact surfaces. In other words, the body shell of the new S550 is a perfect example of the successful integration of a great variety of approaches, aims and requirements. Ultramodern development methods - from crash simulation to digital production planning - helped the Sindelfingen engineers reconcile conflicting objectives and achieve new first-class results. For instance, the static torsional rigidity of the body shell - an indicator of safe and comfortable handling - was improved by about twelve per cent relative to the previous S550. The flexural strength is about six per cent higher than that of the predecessor model. These figures are the result of a careful selection of materials according to the proven Mercedes principle “the right material in the right place.” Steel, aluminium and plastic are the components of the material mix, with steel continuing to play the main role. But here too, the technology is changing: Conventional deep-drawing steels are becoming less important, and in the new Mercedes-Benz S-Class they make up only about 30 per cent of the total. Instead, the experts in Sindelfingen are preferring high or ultrahigh-strength steel alloys, because they achieve a maximum of rigidity with a minimum of weight. Whereas these steels accounted for only six per cent of those used in the predecessor model, for example, they make up about 43 per cent of the total in the new S-Class. In addition, ultra-high-strength alloys are used for the areas of the body important for passenger protection. These steels are shaped when they are still hot and therefore achieve an extremely high tensile strength of up to 1,500 megapascals, which is three times stronger than conventional steels. The side members and B-pillars are made of these ultra-high-strength steels. Sturdy underbody structure with eight side member sectionsThe occupant cell proves to be almost completely resistant to deformation in front, rear or side collisions or when overturning. Passengers can thus be assured of an intact space even when the speed of collision is high. High-strength steels and panels with greater material strength play an important role here, as does the installation of additional support members. A complex and carefully designed underbody structure forms the sturdy foundation of the passenger safety provided in the new vehicle. Eight side member sections, four cross members and a three-part tunnel reinforcement stabilize the passenger compartment in a crash and ensure that impact forces are distributed over a large area. By way of comparison, the predecessor model of the new S-Class was equipped with two continuous side members in the underbody area. Instead of being flat, the sheet metal panels between this multiple-piece supporting structure have a new, asymmetric, arched structure. This structure was precisely calculated and lends the panels a great deal of rigidity, about five times as much as in the predecessor model. Greater rigidity simultaneously means less vibration: The arched structure reduces vibrations to a minimum and thus makes an audible contribution to the exemplary driving comfort of the new S-Class. Mercedes has a patent on the asymmetrically arched floor pan, which was developed by the Sindelfingen engineers together with their colleagues from Daimler-Chrysler research. It is based on insights from the field of bionics. Side structure made of ultra-high-strength steel for the first timeIn a side crash, the main elements that come into play to stabilize the occupant cell are the sturdy side skirts, the B-pillars, the four cross members in the underbody section and a solid steel section below the dashboard. For the first time, Mercedes-Benz is producing the sills and B-pillars with ultra-high-strength steel alloys, which are far superior to all other materials in terms of their tensile strength. By connecting the B-pillars to the structure of the roof frame over a large area, the Mercedes engineers can not only avoid using a transverse piece in the middle of the roof but also reduce the cross section of the A-pillars and thereby improve visibility for the driver. The doors are made of an aluminium-steel combination with interior frames of aluminium die castings and extrusion profiles to reinforce the window frames. The protection from lateral impacts is improved by high-tensile steel reinforcing sections on the inside. The Mercedes engineers paid extra attention to the door hinges as well and developed special high-strength fastening surfaces. This results in a sturdy coupling in the side structure that provides effective protection to passengers during a lateral collision. In addition to a high level of safety, the doors of the new S-Class have functions which make access and egress more convenient. A newly developed hydraulic system ensures that from an opening angle of 15 degrees the doors are arrested in any position — even on gradients or in strong winds. When needed, an electric servo-locking mechanism closes all the doors (and the boot lid). Rear structure for extreme impact stressesAs with front and side impacts, the new S-Class satisfies the most stringent safety requirements for rear crashes too, such as the new U.S. laws specifying an offset crash (70 per cent) with an impact speed of 80 km/h. The occupant cell remains largely undamaged despite this extremely heavy strain, thanks to the meticulously designed deformation zone in the rear. In addition to the aluminium transverse section and the steel crash boxes of the bolted rear module, it consists of two sturdy side members and a cross member in the area of the boot floor. The suspension sub-frame of the rear axle likewise forms an energy-absorbing plane in the event of an impact. The fuel tank is located in the protected area in front of the rear axle. Still greater commitment to pedestrian safetyAnother focus of development for the safety systems of the new S-Class was the issue of pedestrian protection. It is not new for Mercedes-Benz. The engineers of the Stuttgart-based automotive brand have long been making efforts to reduce the risk of injury to the “weakest” road users - pedestrians and those on two-wheeled vehicles. Bodies with flat surfaces, energy-absorbing bumpers, laminated glass windshields, collapsible exterior mirrors, rounded door handles and “recessed” windshield wipers are only a few of the details of the Mercedes passenger cars that serve this purpose. Mercedes’ active safety innovations such as the BAS Brake Assist also make an important contribution to passenger safety, because they can prevent accidents involving pedestrians from happening in the first place or else significantly reduce the speed of impact. Studies conducted by the Sindelfingen engineers confirm this. With the new S-Class, the long-standing Mercedes commitment to pedestrian safety reaches a new high point:
Seat-belt force limiters for front and rear passengersIn addition to the two-stage frontal airbags for the driver and the front-seat passenger, the standard occupant safety system of the new S-Class also includes six lateral air cushions: two sidebags in the front-seat backrests, two sidebags in the rear side panelling and two large windowbags. All the passengers have three-point automatic seat belts. The driver and front passenger seats and the outer seats in the rear are also equipped with seat-belt tensioners and belt force limiters. The force limiter of the front belt straps is adaptive: After attaining a certain maximum level of force, the force limiters switch to a lower level of force – the belts are loosened so that front passengers can plunge deeper into the airbags. This reduces the impact on the chests of the occupants. The newly developed steering column serves the same purpose. During a front-end impact, it collapses like a telescope by up to 80 millimetres. Crash-responsive headrests with additional comfort featuresThe crash-responsive NECK-PRO headrests are another special feature of the safety system of the new S-Class. They reduce the risk of whiplash injuries in a rear collision. Once the sensors have determined that such a collision has occurred and that the impact has exceeded a defined level, the pre-stressed springs in the headrest are released. As a result, the headrest is shifted some 40 millimetres forward and 30 millimetres upward within a split second. In this way, the heads of the front-seat passengers receive support at an early stage. After NECK-PRO has been activated, the headrests can be pushed back to their original position by hand, using the supplied tool, after which they are once more immediately ready for use. Mercedes-Benz is offering the NECK-PRO feature for driver and front passenger as an option in conjunction with extra-comfortable headrests. Mercedes safety after the accident tooThe comprehensive Mercedes safety system PRO-SAFE also takes into account the phase after the traffic accident. To prevent follow-on damage, the fuel supply of the engine is automatically blocked in the new S-Class in accidents above a certain severity. The hazard warning signal also switches on to warn drivers approaching from behind and to prevent new accidents. After an accident in which airbags are deployed, all the side windows open just enough to leave a narrow space through which the interior can be ventilated. At the same time, the door locks are automatically released so that injured passengers can be rescued more quickly. Specially designed crash joints prevent the front and rear doors from becoming deeply wedged during an impact. The passengers can also open the doors after an accident, because Mercedes-Benz uses cables that remain intact after deformation for the internal activation of the door locks. The new S-Class is the first Mercedes passenger car to have markings on the front and rear windows showing the emergency services places where they can cut through the A- and C-pillars in the event of a serious accident to quickly reach injured passengers and provide them with medical care. Good aerodynamics contributes to driving safety tooThe good lift factors at the front and rear axles show that the exemplary aerodynamics of the new S Class not only enable a new record Cd value but also have a positive effect on driving safety. They are up to 14 per cent lower than the corresponding figures of the predecessor model and constitute reliable indicators of high braking stability, secure road-holding and low crosswind sensitivity. The aerodynamics also makes an important contribution to road safety through design details that give the driver an unclouded view through the front side windows during rain. The Mercedes engineers achieve this by deliberately guiding the rainwater backwards, downwards or to the side. In the new S-Class, the side windows, mirror glass and door handles remain for the most part clean, because the rainwater hitting the front window collects in run-off tracks on the A-pillars, is led from there backwards over the roof with the help of the airflow, and then flows downward and away in a channel on the trailing edge of the roof. The housings of the exterior mirrors are shaped in such a way that rainwater flows outward and drips away in a narrow surrounding groove. Light: bi-xenon technology in combination with curve and cornering lightThe headlamps of the S-Class incorporate state-of-the-art lighting technology and make an important contribution to road safety. For the dipped headlights, high-luminosity halogen projection-beam lights come as standard equipment; separate H9 reflector lights are used for the full-beam lights. The indicator lights and side-lights are likewise accommodated in the elegantly proportioned headlight housing, while the fog lamps are integrated into the bumper fascia. Thanks to the driving light assistance system at the windshield, which comes as standard, the head-lights and tail lights switch on automatically when it gets dark, when rain or snow hinders visibility, or when the S-Class enters a tunnel. The optional bi-xenon headlights also come with two new lighting features that provide a significant improvement in driving safety after dark:
The equipment package with bi-xenon headlights, curve lights and cornering lights also includes a dynamic headlight levelling control and a headlamp-cleaning system using a high-pressure water jet. Flashing brake light for preventing rear-end collisionsThe tail lights of the S Class are elegantly separated by two chrome-trimmed body-coloured mouldings. They divide the segments for rear fog lamps, indicator lights, rear lights and brake lights. The adaptive brake light here is a special technical feature Mercedes-Benz has developed to help prevent rear-end collisions: If the driver has to brake hard at a speed of more than 50 km/h, or if he receives support from the BAS Brake Assist in an emergency, the brake lights of the new S Class flash and warn the drivers behind. If the S-Class then comes to a standstill after such an emergency stop, the brake lights once more shine continuously and the hazard warning signal switches on. Options
---- PackagesPremium I - $1250
Premium II - $2850
Premium III (Delayed availability for the S550 Night View Assist; the P3 package is not yet available. Please see your dealer for details.) - $6550
321 AMG Sport-Package - $5600
325 Rear Seat Package - $2900
designo Espresso Edition - $11120
designo Graphite Edition - $11120
designo Mystic White Edition - $11120
---- Prices
Local dealers: Miami Herald
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