First drive: M-class diesel is a ripper sipper!

DIEHARD four-wheel drive enthusiasts would suggest that to go anywhere seriously off the beaten track, only a torque-laden turbo will do – and Mercedes-Benz has obliged with its new $82,900 ML320 CDI.

Slotting the 3.0-litre turbo-diesel V6 between the $79,900 ML350 and $116,900 ML500 petrol variants, Mercedes-Benz expects the oil-burner to account for up to 40 per cent of all ML sales.

Many of those will be derived from city dwellers lured to diesels because of their outstanding fuel economy and sophisticated technology.

This is particularly so in the ML, which weighs more than two tonnes but sips fuel like a parsimonious Presbyterian and sounds like its V6 petrol sibling.

According to Mercedes figures, the turbo-diesel ML will use less fuel than 10L/100km – Mercedes quotes a highway cycle of 7.5L/100km and a city cycle of a still-commendable 12.7L/100km.

Like its petrol siblings, the CDI model utilises Mercedes’ new seven-speed automatic transmission and has a comprehensive list of standard equipment wrapped in a stylish new body which is bigger and roomier than the previous version, but weighs less than the previous 2.7-litre CDI.

The diesel enjoys the same equipment levels as the petrol V6 and runs the same suspension setup, which comprises double wishbones up front and a sophisticated four-link rear with anti-squat and anti-dive characteristics.

Like the V6 petrol engine, the CDI has full-time four-wheel drive, 17-inch alloys (with a full-size spare), electronic stability control, downhill speed regulation, traction control, parking sensors, rain-sensing windscreen wipers, dual front, side and curtain airbags, climate-control air-conditioning, six-disc CD stereo, cruise control, split-fold rear seats and multi-function steering wheel.

Also used on the Jeep Grand Cherokee, the turbo-diesel is a third-generation common-rail direct-injection unit with the latest in piezo injectors. In the ML, it develops 165kW at 3800rpm and 510Nm from 1600rpm, endowing the vehicle with a top speed of 215km/h and claimed 0-100km/h acceleration of 8.6 seconds.

The V6 turbo-diesel replaces the previous in-line five-cylinder engine of the ML270 CDI but because of its lightweight, compact construction it is about the same weight as the five-cylinder engine.

An Off-Road Pro package is available for a whopping $10,150 and utilises height-adjustable Airmatic air suspension with a two-speed transfer case and differential locks.

Other options include an $8000 "luxury pack", $1500 "chrome pack" and a $9980 "sports pack".

M-class pricing:

ML350 - $79,900
ML320CDi - $82,900
ML500 - $116,900

M-class options:

Luxury pack - $8000 (ML320CDi/ML350)
Chrome pack - $1500 (ML30CDi/ML350)
Sports pack - $9980 (ML320CDi/ML350)
Off-Road Pro - $10,150 (ML320CDi/ML350)
Off-Road Pro - $4900 (ML500)