Mercedes S400 Hybrid (2008) | CAR Magazine

Mercedes S400 Hybrid (2008)

Published: 01 February 2008 Updated: 26 January 2015

Hello hybrid. CAR Magazine has caught Mercedes’ first hybrid model testing in Scandinavia before a European launch in mid-2009. This is the S400 Hybrid, and our spy shot under the big limo’s bonnet appears to show Merc’s second big step towards going green – the first was their NOx-busting Bluetec technology.

The S400 Hybrid will come with a 274bhp petrol V6, but mated to a hybrid module the S400 will have a total of 295bhp and 277lb ft. That means 0-62mph in 7.3 seconds but more importantly 35.8mpg and just 190g/km CO2. The equivalent 262bhp S350 will only do 28mpg while producing 242g/km CO2.

So what’s the hybrid technology like?

Somewhat complicated but there’s a disk-shaped electric engine that also acts as the starter motor meaning this S-class will have a stop/start system. The electric motor also helps to boost performance when accelerating, while under braking it acts as a generator, recovering braking energy. This energy is stored in lithium-ion batteries mounted in the engine compartment.

The technology has been developed in conjunction with BMW and GM. The Amercians have already shown the hybrid system in various SUVs, while BMW will use the technology in the new 7-series and X6.

And if I want my limo a little cleaner…

…You’ll have to wait a little longer. Mercedes is also readying two diesel hybrids, the S300 and S400. The S300 Bluetec Hybrid will appear first in 2010 and offer a frankly stunning 52.3mpg. Combined with Bluetec technology the S300 will also only produce 142g/km CO2. There’s no word from Mercedes yet on what diesel engine will power the S300, but the all-new E-class will come in 2010 as an E300 Bluetec powered by a 2.2-litre four-cylinder engine. Whether S-class buyers will accept anything less than six cylinders remains to be seen.

If you still want to be clean and green though, but with a little more power then the S400 Bluetec Hybrid will be along after 2010. Combined with the hybrid module the diesel V6 will produce 261bhp and 464lb ft, while still averaging 48.7mpg and emitting 154g/km CO2

How else are Merc going green?

Later this year we’ll see a CNG-powered B-class, and there’s already diesel and petrol hybrid Smart cars on the road, as well as electric versions. The M-class (which is facelifted this year) will gain hybrid power in 2009, 2010 will see a fuel-cell B-class, and 2011 will bring us a C300 Bluetec Hybrid.

In the meantime 2008 will see Bluetec technology reaching the R, ML and GL in 320CDI form. Whether these cars make it to the UK is another matter, as despite an 80 percent reduction in NOx, Bluetec technology currently increases CO2 output by a few points and therefore makes the system useless under Britain’s current CO2 ratings system.

Beyond Bluetec and hybrids Mercedes’ third step will be the Diesotto engine due in 2014. Read all about it here.

By Ben Pulman

Ex-CAR editor-at-large