New York show: Mercedes upgrades S-class

MERCEDES-BENZ used this week’s New York Auto Show to unveil the first petrol-electric versions of its S-class flagship sedan and M-class luxury SUV, but neither hybrid model will become available in Australia.

While the ML450 Hybrid and S400 Hybrid, the first hybrid production vehicles from Mercedes, have not been engineered in right-hand drive, the latter has emerged in the Big Apple as part of a facelifted limousine line-up that goes on sale here from August.

Representing a midlife model makeover for the German maker’s W221-series S-class that first appeared four years ago, the 2009 S-class goes on sale in Europe in June.

With 270,000 examples sold globally since 2005, making it “the world's most successful luxury saloon”, the W221 is the latest in a line of S-class models that stretch back to the 220 model of 1951, since when around 3.3 million versions have been delivered.

In other markets, the revised S-class range will comprise the new entry-level S350 CDI BlueEfficiency, priced in Germany at €73,006 ($A136,785) plus taxes, followed by the S350 at €76,160 ($A142,694) plus taxes.

In Australia, the current S-class line-up opens with the six-cylinder S320 CDI diesel and S350 petrol, both priced at $198,810.

Europe’s 2009 S-class range will also include the V8 petrol S450, V8 diesel S450 CDI and the new S400 Hybrid that will be priced between the two at €85,323 ($A159,862) plus taxes, along with the S500 and (AMG) S63 V8s and the S600 and (AMG) S65 V12s.

In the absence of the S350 CDI BlueEfficiency, S400 Hybrid, S450 and S450 CDI, the Australian S-class range will make do with more efficient engines and a number of new (optional) camera and radar-based driver assistance systems from the new E-class, including Adaptive Highbeam Assist, Lane Keeping Assist, Speed Limit Assist, Night View Assist Plus and the Attention Assist drowsiness detection function.

From top: S400 Hybrid, ML450 Hybrid and S600 (bottom).

While it doesn’t match the average economy of the turbo-diesel S350 BlueEfficiency (7.6L/100km), the S400 Hybrid (7.9L/100km) is claimed to be the world’s most economical luxury petrol sedan – as well as the first to incorporate a standard-production hybrid drive with a lithium-ion battery. It does, however, return average CO2 emissions of 186g/km, allegedly making it the “CO2 champion of the luxury class”.

“The S400 Hybrid is an important milestone on the way to emission-free mobility,” said Daimler AG CEO and head of Mercedes-Benz Cars, Dr Dieter Zetsche.

“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.” The S400H is powered by a modified 3.5-litre V6 petrol engine that generates 205kW, mated to a 15kW/160Nm electric motor and a unique version of the brand’s 7GTronic seven-speed automatic transmission. Braking energy recuperation and idle-stop functions are part of the system.

The 3.0-litre diesel V6-powered S350 CDI BlueEfficiency, meantime, produces 173kW and features fuel-saving additions like fully an enclosed underbody and decoupling of the seven-speed auto at standstill.

Also continuing in other markets will be the 235kW 4.0-litre turbo-diesel V8-powered S450 CDI, the 200kW 3.5-litre V6-powered S350 (also available with 4Matic), the 250kW 4.7-litre petrol V8-powered S450 (4Matic), the 285kW 5.5-litre petrol V8-powered S500, the 380kW twin-turbo 5.5-litre petrol V12-powered S600.

The 386kW 6.2-litre S63 AMG and 450kW 6.0-litre twin-turbo V12 S65 AMG also continue, while Benz’s 4Matic all-wheel-drive system will be available with the S350 CDI, S350, S450 and S500 in Europe.

Apart from Attention Assist, a new Active Body Control (ABC) system will be standard on the S600 flagship, while a Torque Vectoring Brake function, which brakes the inner rear wheel during cornering to improve stability, will be standard.

Similar to the new infotainment system that will appear on the next-generation Jeep Grand Cherokee is a new Splitview function for the Comand central control system which will be an S-class option. As with the 2011 Grand Cherokee, the new display system allows the driver and front passenger to view different systems, such as satellite-navigation and a DVD movie, on the same screen simultaneously.

Finally, the 2009 S-class will introduce the option of LED daytime driving lights, which will be standard on the S400 Hybrid and S600.

Meantime, Mercedes-Benz Australia says the ML450 Hybrid, which is the first product of a two-mode hybrid drive partnership between Daimler, BMW, Chrysler and General Motors, will not be sold here in its current guise.

“The ML hybrid won’t come to Australia at this stage – not at this stage,” said the company’s senior manager of corporate communications David McCarthy.

“It wasn’t engineered for right-hand drive, so it was hard to make a business case for it,” he said, before adding that another future version of the ML450 Hybrid would eventually be sold in Australia – but he could not divulge when.

“The ML450 Hybrid we’ve revealed is different to the version we will get. The actual model revealed here, no, but subsequent models, yes,” said Mr McCarthy.

For the record, Daimler said development of the ML450H comprised a total of four million kilometres, including locations like the Arctic circle, desert regions and humid tropics.

The ML’s full two-mode (or parallel, meaning both the engine and motor drive its wheels) hybrid drive system is claimed to offer the performance of a V8-powered AWD SUV, with fuel consumption and emissions levels that have been reduced by 60 per cent.

It is powered partly by a “consumption-optimised” Atkinson-cycle 205kW/350Nm 3.5-litre petrol V6, in which the intake valves are kept open slightly longer between the intake and compression phases to improve thermal efficiency while reducing fuel consumption and untreated emissions. The Atkinson V6 features modified cylinder-heads, pistons and camshafts.

The ML450 Hybrid’s combustion engine is assisted by two electric motors mounted at either end of the transmission housing – a 62kW/235Nm unit closest to the V6 and a 60kW/260Nm unit at the other end, which provides start-off power and a “booster” function.

Apart from two motors, the transmission houses three planetary gear sets and four clutches and, unlike most single-mode hybrids, comprises conventional mechanical ratios: ECVT 1 mode (Electric Continuously Variable Transmission) for moving off or at low speed and ECVT 2 mode at higher speeds.

The alternator and starter motor functions are integrated in the two electric motors and, like the air-conditioning compressor and steering servo pump, are therefore no longer connected to the combustion engine’s drive belt.

The entire system is charged by an 83kg rear-mounted 288-volt liquid-cooled nickel-metal-hydride battery pack.

Like Toyota’s pioneering Prius, the ML450 Hybrid features a number of different operating modes, including a variable hybrid mode for city and freeway driving silent, all-electric moving off and motoring a “booster” function for fast acceleration energy recuperation and the start/stop function.

At standstill, the petrol V6 is switched off and the air-conditioning and power steering systems continue to operate under electric power. Electric-only power is employed during gentle take-offs, while the V6 is also employed during hard acceleration.

The hybrid SUV differs from the standard M-class only via a new bonnet, ‘HYBRID’ rear lettering and ‘BlueEFFICIENCY’ wing labels, but remains unchanged inside.