Revised S-Class highlights efficiency

Diesel engines are so 19th Century. If you want 'green' credentials these days, you have to offer hybrid-drive vehicles with lithium-ion batteries. Mercedes-Benz is doing just that with the upgraded S-Class range, which will incorporate a petrol/electric model, the S 400 Hybrid.

According to the manufacturer, the S 400 Hybrid will be the flagship variant in the range, but will use just 7.9L/100km of fuel in combined-cycle testing. Appeasing environmentally-sensitive buyers too, the car emits 186g/km of CO2.

"Our first series production hybrid car exemplifies Mercedes-Benz's long-standing development strategy geared towards sustainability, with its clearly defined aim of producing economical and environment-friendly premium cars without compromising on safety, comfort and superior performance," says Dr Dieter Zetsche, CEO of Daimler AG and head of Mercedes-Benz Cars.

The S 400 Hybrid bundles a 3.5-litre petrol V6 that produces 205kW of power, with a 15kW electric motor and lithium-ion battery storage. Benz claims it's the first such use of lithium-ion battery technology in a production car. Based on the S 350, the S 400 runs power through a modified version of the 7G-Tronic automatic transmission and relies on the electric motor to recover kinetic energy and convert it to electrical energy during braking. In addition, the hybrid S-Class features an auto-stop/start system to run the petrol engine only when required. With most of the extra hardware located under the bonnet, boot space is unaffected, making the hybrid variant a potentially more attractive proposition than the Lexus LS 600h (more here).

Benz isn't leaving its traditional diesel buyer base behind either. The S 350 BlueEfficiency model actually undercuts the petrol hybrid with a fuel consumption figure of 7.6L/100km and CO2 emissions of around 200g/km. Powered by a 3.0-litre engine also found in the all-wheel drive S 350 CDI 4Matic, the S 350 develops 173kW. As for the S 400, the diesel variant drives through the 7G-Tronic automatic transmission, which automatically 'decouples' from the engine at standstill for further efficiency gains.

In all, eight different engines power the 2009 model range and the manufacturer claims fuel consumption figures have been reduced by as much as seven per cent. Some of the efficiency gains are the result of aerodynamic changes, which also reduces wind-related NVH.

The three variants mentioned will sell alongside the S 450 CDI diesel, displacing 4.0 litres and developing 235kW of power; the S 350 petrol (available in all-wheel drive guise also, as the S 350 4Matic), with 200kW 3.5-litre V6; the S 450/S450 4Matic, producing 250kW of power from its 4.7-litre V8 and the S 500/S 500 4Matic variants, generating 285kW from a 5.5-litre V8. Topping the range is the S 600, which features a 380kW twin-turbo 5.5-litre V12 capable of propelling the car from a standing start to 100km/h in 4.6 seconds. Tuning partner AMG has its own contribution to make, with S 63 AMG and S 65 AMG models available too.

Among the new features the S-Class will adopt or carry over from the new E-Class are: Adaptive Highbeam Assist, Lane Keeping Assist, Speed Limit Assist, Night View Assist Plus, Attention Assist and Active Body Control (automatic crosswind stabilization). Most of these systems are self-explanatory and, indeed, have been introduced in competitive models from Audi and BMW (more here).

Attention Assist ensures that drivers are alerted if steering input indicates that the driver is fatigued. Active Body Control is fitted as standard to the S 600 and relies on the stability control system's lateral G-force sensors to compensate for side winds.

"The aim in developing these systems was to prevent particularly common and serious collisions," says Dr. Thomas Weber, member of the board of management at Daimler AG. "With this concept, the S-Class not only protects its own occupants but also plays a key role in enhancing safety for other motorists."

Mercedes-Benz has improved the in-car entertainment and information systems by integrating an SD memory card slot in the Comand system and introducing a new feature ('Splitview') that allows front-seat passenger and driver to watch different content on the same screen. The example provided by Benz was the driver reading a map while the passenger watches a film on DVD.

Other new or revised features -- new to the S-Class at least -- include a modified Bluetooth interface and connections for iPod and USB stick.

The 2009 model S-Class can be identified by a subtle facelift comprising changes to the grille, bumpers and exhausts. All variants now come with standard bi-xenon headlights and LED tail lights.

Local deliveries of the revised model range are due to commence from late September and Mercedes-Benz Australia will announce specifications and pricing at or around that time.