Mercedes ML 350 CDI BlueTEC Sport

More than a million Mercedes M-Class models have been sold around the world since the original arrived in 1997, so it’s no surprise that the company has played it safe with the styling of the all-new MkIII car.

Familiar M-Class visual cues are carried over, like the rear quarter panel windows that blend into the tailgate glass and the upright grille. Yet the sculpted door panels hint at Mercedes’ sleek CLS four-door coupé, while some of the lines clearly take their inspiration from the sober-suited E-Class. Overall, the look is solid rather than spectacular, although our Sport trim test car still attracts attention with its bodykit and big wheels.

Inside, the Mercedes is smart and very businesslike. An attractive sweeping dash, black gloss trim and large, deep-set dials  dominate, while quality has taken a leap forward compared to the outgoing car. There’s a big range of wheel and seat adjustment and you immediately feel at home thanks to a lofty view of the road from the driver’s seat.

The logically laid-out controls are a big plus, while Mercedes’ COMAND rotary controller is a new feature for the M-Class. Having the gear selector on a stalk frees up space for a large central stowage bin, which is complemented by big door pockets.

The new car has the same wheelbase as its predecessor, but it’s longer and wider, so passenger space is a match for the Porsche, with even tall adults able to travel in the back seats in complete comfort.

The 690-litre boot is the biggest on test, while the rear seat layout is cleverly designed. For starters, the seats recline, which helps passenger comfort, but the bases also tumble forward against the front seats. This allows the seatbacks to fold fully flat, giving a huge 2,010-litre load space that’s only beaten on this test by the Land Rover Discovery.

Better still, on the move the upmarket, comfortable and very practical M-Class cabin isolates you and your passengers from the outside world, with road and wind noise virtually non-existent. Mercedes customers expect top-notch refinement and, helped by the smoothness of the revised 3.5-litre V6 diesel, they won’t be disappointed.

The engine features Mercedes’ BlueTEC technology, which includes a smooth stop-start system, and is mated to a new 7G-Tronic Plus seven-speed auto gearbox. Claimed economy has risen from 32.5mpg to 39.2mpg and CO2 emissions of only 189g/km match those of the efficient Porsche.

With 255bhp and 620Nm of torque (up 27bhp and 81Nm on the old engine), the Mercedes has the performance to match the Cayenne. At a wet test track, both cars offered unbreakable traction and completed the 0-60mph test in only 7.2 seconds, while their in-gear response and pick-up in kickdown mode was equally punchy. The Porsche and Mercedes both felt more responsive than the much heavier Land Rover.

But it isn’t just the ML 350’s smooth-shifting auto box and effortless overtaking urge that are worthy of note. On twisty roads, its taut body control and safe handling also stand out, while the ride is impressively composed and comfortable. 

However, it’s important to note our car had over £5,000 worth of chassis upgrades. A £3,240 adaptive roll control system was matched to Mercedes’ £1,775 air suspension, which includes adaptive damping and allows the ride height to be raised for off-roading. Cars with standard steel springs have a firmer ride.

And thanks to its hill descent control and an off-road setting for the stability system, the ML 350 will only be shown a dirty pair of heels by the Discovery in the worst off-road conditions. In isolation, the M-Class is a big step forward over the car it replaces. But is that enough to beat these toughest of rivals?

Details

Chart position: 3
WHY: Mercedes says new M-Class is as comfortable, composed and refined as ever, but with lower emissions and better economy.