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New diesel variant with V8 power: The S 420 CDI flagship diesel model makes its debut

PHOTO (select to view enlarged photo)
The new eight-cylinder engine powers the E420CDI to the top of this market segment in terms of dynamics and smooth runnings characteristics.

PHOTO (select to view enlarged photo)
Higher torque, lower exhaust gas backpressure under full load and low smoke output at high speeds are the principal advantages of variale turbochargers.

PHOTO (select to view enlarged photo)
The new eight-cylinder engine powers the E420CDI to the top of this market segment in terms of dynamics and smooth runnings characteristics.
Stuttgart, Dec 06, 2006
Mercedes-Benz is extending its S-Class range with another diesel variant, the S 420 CDI. The new eight-cylinder model is powered by a state-of-the-art V8 CDI engine developing 235 kW/320 hp and 730 newton metres of peak torque. This latest addition to the model line-up means that the luxury saloon range from Mercedes-Benz now encompasses two diesel engines, six petrol models and two body variants, along with the new 4MATIC all-wheel-drive system. The new S 420 CDI is available to order now, with deliveries to customers due to start in December 2006. The short-wheelbase model is priced at € 84,448 (net price € 72,800) and the long-wheelbase version at € 92,104 (net price € 79,400).

The new V8 model's strengths are effortlessly superior performance combined with moderate fuel consumption. The S 420 CDI powers from 0 - 100 km/h in 6.6 seconds and goes on to reach 250 km/h (electronically governed), all while returning fuel consumption figures below the magic ten litre threshold, burning just 9.4 to 9.6 litres of diesel per 100 kilometres on the NEDC cycle. With a fuel tank capacity of 90 litres, this equates to ranges approaching the 1000 kilometre mark.

Such impressive figures are down to the highly advanced eight-cylinder turbodiesel engine under the bonnet: from its 3996 cc displacement, the CDI unit with four-valve-per-cylinder technology delivers a maximum output of 235 kW/320 hp at 3600 rpm and a peak torque of 730 newton metres, which is on tap from 2000 rpm. Third-generation common-rail high-pressure injection technology with a maximum injection pressure of 1600 bar and an ignition pressure of 175 bar ensures efficient combustion. Optimised flow dynamics for the best possible gas cycle and twin turbochargers with variable-nozzle turbines promise high power and torque delivery. As many as five injections of diesel fuel per injection cycle, special orifice nozzles, piezoelectric injectors and highly effective exhaust gas recirculation all help to lower emissions significantly. The new V8 powerplant is equipped as standard with a maintenance-free diesel particulate filter to cut untreated emissions even further, and also complies with the EU4 emissions standard. The engine development team was able to reduce noise levels by optimising the chain drive and fitting a rigid crankcase with large engine bearings as well as extra acoustic covers. The square bore-to-stroke ratio combines with a counter-rotating balancer shaft for outstandingly smooth operation.

Power transmission in the S 420 CDI is handled by the standard-fitted 7G-TRONIC automatic transmission with a DIRECT SELECT lever on the steering column, plus steering-wheel gearshift buttons. Not only does this combination guarantee that the tremendous reserves of power and torque are harnessed to optimum effect, the seven-speed automatic transmission's wide ratio spread is also perfect for motoring at low rev speeds – ideal for quiet, fuel-efficient travel. The top-of-the-range S-Class diesel model comes as standard with AIRMATIC air suspension including the Adaptive Damping System (ADS) and an all-round self-levelling function, while the latest-generation Active Body Control (ABC) can be specified as an option.

Broader model range than any other competitor in the world

The arrival of the new S 420 CDI sees Mercedes-Benz further expand its S-Class range to eleven models, making it the broadest luxury-segment model selection in the world. The two diesel variants, the S 320 CDI and S 420 CDI, line up alongside a choice of six petrol-powered models, including the S 450 whose new eight-cylinder engine extracts 250 kW/340 hp and 460 newton metres of torque from its 4.6-litre displacement. The line-up is headed by two extra dynamic and exclusive AMG high-performance models. The redeveloped 4MATIC all-wheel drive can be ordered for three of the S-Class variants. All models are available with either the short or the long wheelbase; the long version is standard for the V12 models.

The S-Class model range at a glance:

  Cyl. cc kW/hp
at rpm
Nm at
Trans-mission 0-100 km/h s Top speed km/h l/100 km
NEDC comb.
S 320 CDI* V6 2987 173/235
7G-TRONIC 7.8 250 8.3-8.6
S 420 CDI V8 3996 235/320
7G-TRONIC 6.6 250 9.4-9.6
S 350**

V6 3498 200/272
7G-TRONIC 7.3 250 10.1-10.3
S 450*

V8 4663 250/340
7G-TRONIC 5.9 250 11.2-11.5
S 500*

V8 5461 285/388
7G-TRONIC 5.4 250 11.7-12.0
S 600


5513 380/517
5-speed automatic 4.6 250 14.3
S 63 AMG V8 6208 386/525
7G-TRONIC 4.6 250 14.9
S 65 AMG V12 5980 450/612
5-speed automatic 4.4 250 14.8
* Also available with 4MATIC all-wheel drive; ** Also available with 4MATIC all-wheel drive from mid‑2007

High global demand for the new Mercedes-Benz S-Class

As the top-selling luxury model worldwide, the S-Class comfortably outstrips the sales figures for its rivals in every region of the world. In the first ten months of 2006, over 70,000 new luxury saloons were delivered to customers, the highest figure ever in the history of the company. On diesel sales too, the S-Class is again the No. 1 in the luxury segment, and Mercedes-Benz is now adding an exceptionally powerful model to the diesel line-up in the form of the new S 420 CDI. It is the successor to the V8-powered S 400 CDI that proved so popular in the previous S-Class range.

PRE-SAFE® as standard, Brake Assist PLUS as an option

The unrivalled PRE-SAFE® occupant protection system also forms part of the standard specification for the new leading S-Class diesel model. PRE-SAFE® is able to recognise potential accident situations as soon as they start to develop: if the rate of braking deceleration exceeds a certain threshold or there is a risk of skidding, the system triggers anticipatory measures, pulling the front seat belts taut and, if necessary, raising the front passenger seat backrest into a more upright position. On models fitted with the optional multicontour seats, the air cushions are inflated too so that they help to brace the front passenger and the occupants in the rear. The sliding sunroof (optional) is closed as a further precaution.

Brake Assist PLUS (BAS PLUS) can be specified as an optional extra. It uses radar to track any vehicles ahead of the car and warns the driver if the S-Class gets too close to the vehicle ahead or is approaching it too quickly. If there is a risk of collision, the system instantaneously calculates the optimal braking power required and makes this available immediately as soon as the driver starts braking, even if the brake pedal is not pressed hard enough. The result is a significant reduction in the number of rear-end collisions. Combining the new Brake Assist PLUS with PRE-SAFE® allows occupant protection to be taken to even greater heights. The introduction of PRE-SAFE® has made Mercedes-Benz the first automotive brand in the world to fit as standard such an extensive safety system that swings into action ahead of a potential accident.

PRE-SAFE® Brake system with the very latest radar technology

For the first time ever in the S-Class, Mercedes-Benz is offering a complement to this multi-award-winning anticipatory protection system, in the form of the newly developed PRE SAFE® Brake system. This works in unison with Brake Assist PLUS (BAS PLUS), which issues drivers with a visual and an acoustic warning of an impending rear-end collision with a vehicle ahead and automatically calculates how much braking power is needed to prevent the collision. The braking power is boosted as required the instant the driver presses the brake pedal. However, should the driver fail to heed the warnings and the risk of an accident become acute, the PRE-SAFE® Brake system automatically initiates partial braking to decelerate the S-Class with around 40 per cent of maximum braking power. This partial self-braking – in effect a "virtual" crumple zone – is a further tangible prompt for the driver to take action. If the brake pedal is pressed at this stage, maximum braking power will be applied. Depending on the particular situation, this could be enough to avert a collision at the last moment. If it is not, the severity of the impact will at least be mitigated and the risk of injury to the occupants therefore lessened thanks to the PRE-SAFE® Brake. Mercedes-Benz offers BAS PLUS and the PRE SAFE® Brake as an option in conjunction with DISTRONIC PLUS proximity control.

DISTRONIC PLUS: assistant for driving in stop-start traffic

The radar-assisted DISTRONIC PLUS system is operative in a speed range from zero up to 200 km/h and enables even more comfortable motoring. In stop-start traffic, DISTRONIC PLUS keeps the new S-Class at the programmed distance from the vehicle ahead, automatically brakes the saloon to a halt and accelerates back up to the stored speed upon the driver's command. In this way, the assistance system relieves the strain on the driver whilst giving a major boost to driver-fitness safety. The Brake Assist PLUS and DISTRONIC PLUS package also comprises a Parking Assist system, which uses the radar technology to give advance warning of an imminent collision at the front or rear of the vehicle when parking.

Extensive, stylish standard specification

The standard specification for the new S 420 CDI includes a host of high-tech systems which are designed to enhance levels of safety and comfort – such as the ADAPTIVE BRAKE system, seats with 12-way electrical adjustment, COMAND with DVD player, DIRECT SELECT gearshift and automatic climate control.

An excerpt from the list of standard equipment:

  • Adaptive airbags for driver and front passenger
  • Adaptive brake lights
  • AIRMATIC with Adaptive Damping System (ADS)
  • 7G-TRONIC automatic transmission
  • ADAPTIVE BRAKE system with Brake Assist
  • COMAND with CD/DVD player and PCMCIA slot
  • Diesel particulate filter
  • DIRECT SELECT gearshift
  • ESP®
  • Parking brake, electrically operated
  • Belt force limiters for the front and outer rear seats
  • Belt tensioners for all seats
  • Automatic climate control
  • 17-inch five-spoke light-alloy wheels
  • Multifunction steering wheel
  • NECK-PRO head restraints
  • Speed-sensitive power steering
  • Tyre pressure loss warning system
  • Automatic comfort-fit seat belts for the front and outer rear seats
  • Sidebags front and rear
  • Tinted, sound-insulating and infrared-reflecting laminated glass all round
  • Windowbags

Supplementary standard equipment features for the extended wheelbase version of the S 420 CDI include:

  • Leather upholstery
  • Electrically operated sunblind for the rear window
  • Electric tilting/sliding glass sunroof with PRE-SAFE® function
  • Front passenger seat also electrically adjustable from the rear
  • Rear bench seat with electrically adjustable outer seats and PRE-SAFE® positioning function for the outer seats and the outer head restraints
  • Heated front and rear seats