MERCEDES-BENZ has appointed a diesel model as its C-class range-topper in Australia.

Launched this week, the strong-performing C320 CDI is priced from $92,800, making it the highest-ranked C-class – at least until the tyre-searing C63 AMG model touches down next March.

The C320 CDI is the second diesel model in the C-class range, with the C220 CDI part of the initial line-up launched in July alongside two petrol models.

While the C220 is a four-cylinder turbo-diesel, the C320 is the latest-generation V6 turbo-diesel.

The 3.0-litre common-rail engine, which includes a piezo injection system that pumps fuel in at a maximum of 1600bar, generates 165kW and 510Nm, the latter available between 1600rpm and 2800rpm.

Mercedes has replaced the diesel’s traditional heavy cast-iron block with one made from aluminium, although it also has cast grey-iron cylinder liners. The company said that such changes kept the engine weight capped at 200kg.

Even so, the C320 CDI is still the heaviest C-class at 1700kg, compared to the 1585kg C220 CDI, the 1555kg C280 and the 1490kg C200 Kompressor.

stackmerc.jpgCombined with the standard 7G-Tronic automatic transmission, the new diesel engine enables the C320 to dash from 0-100km/h in just 6.9 seconds.

Official ADR81/01 economy figures show the C220 CDI also uses just 7.4L/100km.

Mercedes has fitted the C320 CDI with all the gear that comes standard with the petrol C280 model, but has also added three-zone climate-control for extra comfort.

Other standard equipment includes 17-inch alloy wheels, rain-sensing wipers, a leather-trimmed steering wheel and transmission knob, a multi-function steering wheel (with cruise control), leather trim and power-operated front seats.

Like the C280, the new diesel model is fitted with the Command APS premium central information and entertainment system that includes satellite-navigation.

Standard safety gear on the C320 CDI includes electronic stability control, eight airbags, Mercedes’ Pre-Safe anticipatory occupant protection system, and anti-whiplash head restraints.

Customers can choose between the traditional Elegance styling, complete with gun-sight bonnet emblem, or the sportier Avantgarde specification which includes darker woodgrain trim, a deeper front bumper and more aggressive grille featuring a large tri-star badge.

The C-class range now consists of the entry-level C200 Kompressor at $56,990, the C220 CDI at $60,274, the C280 at $84,974 and the C320 CDI at $92,800.