Spied: 2013 Mercedes S-Class

This is the latest spy pics of the next Mercedes S-class in testing.

Mercedes is preparing to give its new S-class some curves — although the firm has done its best to disguise it by covering this early test hack with extensive cladding.

Due by the end of 2012, this next-generation S-class — codenamed W222 — is expected to adopt key styling cues from the F700, the swoopy concept car displayed at the Detroit show in 2007.

This mule is clearly based on a current model, although the blacked-out headlamps, dummy front grille, new front bumper and a sizeable disguise over the boot and tail-lights hint at the key areas for the new look.

At the heart of the revised range will be Mercedes’ new V6 and V8 MoVe petrol powerplants, which will trickle out across the firm’s line-up from this autumn.

The V6 has a narrow-angle block, stop-start technology and revised direct injection that improves fuel economy over the old-spec unit’s by as much as 24 per cent.

The V8 engine replaces the old 5.4-litre motor by reducing capacity (to 4.6 litres) but adding twin turbochargers. It has 429bhp, a 12 per cent increase, and 32 per cent more torque, but improved fuel economy and CO2 emissions.

Diesel options are likely to include the smallest oil-burner ever offered in the model. Called S250 CDI, it will have a 204bhp 2.1-litre, four-cylinder motor. The same engine could also be used as the basis for a mild hybrid variant to sit alongside a petrol hybrid that will be based on a direct-injection V6 and new battery technology from LiTec.

The next S-class had been expected to use Mercedes’ radical Diesotto powerplant. Claimed to blend the characteristics of petrol and diesel engines, the unit has been showcased in a current model.

However, sources in Germany say the motor’s development has been knocked back in the schedule to allow Mercedes to fast-track work on hybrid technology. It’s now unlikely to appear in an S-class for at least two generations.

Thanks to: Autocar