A new high-tech six speed automatic transmission has been added to the latest Peugeot 407 HDi turbo diesel Sedan and Touring models.

The AM6 tiptronic gearbox replaces the existing four speed transmission and is also used in the new Peugeot 407 Coupe which has just gone on sale in Australia.

Despite the improvement to the stylish Peugeot, there are no increases in the recommended retail price.

The 407 HDi diesel is $48,190, while the 407 HDi Touring model with the same engine and transmission retails at $51,190.

The compact new transmission improves both performance and economy, with the six gears exploiting the thrifty HDi diesel engine to the full.

Compared to the previous transmission, the lower first gear boosts the performance of the Peugeot from a standstill, while fifth and sixth gears not only reduce mechanical noise but also lowers fuel consumption, and makes cruising even more comfortable.

The compact new automatic is controlled by an integral computer and enables the already frugal HDi diesel engine to use even less fuel. With a city cycle of only 10.0 litres per 100 kms and a highway cycle of only 5.5 litres per 100 kms, the 407 HDi certainly is a smart choice for those looking to save money at the service station.

Three modes are offered by the transmission. In full automatic setting, the transmission makes optimum use of engine torque. Sport mode, which is accessed by a button, raises the change-up points to improve performance. Finally, the sequential mode affords manual over-ride of all six gears. The Tiptronic control allows the driver to select ratios rather than leaving the transmission to do the changes.

The 2.0-litre DW10 BTED4 diesel employs a Garrett variable geometry turbocharger and air to air intercooler. It produces 100 kW of power at 4,000 rpm and a generous 320 Nm of torque at only 2,000 rpm.

When the engine is under full load at between 1,500 rpm and 3,200 rpm, peak torque can be boosted to 340 Nm at 2,000 revs, thanks to an over-boost function.

Peugeot 407 Touring (HDi)