BMW belts out four hi-po M diesels

BMW has revealed its initial launch range of four bahnstorming new M-badged performance diesel models powered by a bullocking new 740Nm triple-turbo diesel six, including the X5 and facelifted X6 crossovers – both of which will arrive here in just six months - and the latest 5 Series sedan and wagon, which for now won’t be sold here.

The first diesel models from the Bavarian maker’s hallowed M brand, which also once famously said it would never produce a turbocharged M5 or a V8-powered M3, form the basis of the new ‘sub-M’ BMW M Performance Automobiles line-up announced earlier this month.

Due to make their global debut at the Geneva motor show in March and positioned in terms of both price and performance between existing top-shelf petrol-powered models and full-blown M versions of the X5, X6 and 5 Series, all four new M models will come with comprehensive body, chassis and aerodynamic upgrades.

That is in addition to a ballistic new 3.0-litre inline six-cylinder diesel engine, which BMW says was developed exclusively for BMW M Performance Automobiles and – while still bearing the ‘TwinPower Turbo’ name - incorporates three high-pressure variable-geometry turbochargers, plus common-rail direct piezo-injection with injection pressure of up to 2200 bar.

Left: BMW X6 facelift, X5 M50d and M550d sedan and wagon.

Matched exclusively with an M-tuned eight-speed automatic, it churns out no less than 280kW of power between 4000 and 4400rpm (equating to a specific output of 93.6kW per litre), along with some 740Nm of torque where it’s most useful – between 2000 and 3000rpm – although the all-aluminium tri-turbo six can also rev to 5400rpm.

Despite offering “instantaneous responses and outstandingly dynamic power delivery”, BMW claims the addition of EfficientDynamics technologies such as a fuel-saving idle-stop function and the driver-miser Eco Pro efficiency coaching system make all four oil-burning M models outstandingly efficient.

To be positioned between the existing 300kW/600Nm petrol V8-equipped X5 xDrive50i ($134,000) and the 408kW/680Nm X5 M ($178,200), the new X5 ‘M50d’ sprints to 100km/h in a claimed 5.4 seconds yet returns combined European fuel consumption of just 7.5 litres of diesel per kilometre and emits 199 grams of CO2 per kilometre.

Slightly quicker but thirstier, the new X6 M50d will slot similarly between the X6 50i ($149,400) and X6 M ($185,400), as part of a facelifted X6 line-up also revealed ahead of its Geneva debut alongside the all-new M6 and 6 Series GranCoupe.

After more than 150,000 global sales in three years the upgraded X6 range will bring a revised front-end with fresh grille and foglight designs, reshaped LED tail-lights, the segment-first option of LED headlights (standard for the X6 M) and new wheels, leather trims and paint finishes.

The X6 M50d hits 100km/h in a claimed 5.3 seconds while consuming 7.7L/100km and emitting 204g/km, making it almost as efficient as the 225kW/600Nm twin-turbo diesel X6 40d (7.5L/100km) and 180kW/540Nm single-turbo diesel X6 30d (7.4L/100km).

Likewise, the new M550d sedan will be positioned between the 550i sedan ($179,900) and the new M5, which arrives here next month and offers more peak power but less torque.

It sprints to 100km/h in a claimed 4.7 seconds (M550d Touring: 4.9 seconds), returns 6.3L/100km (Wagon: 6.4L/100km) and emits 165g/km (wagon: 169g/km), making it as efficient as the twin-turbo 535d and just three-tenths slower to 100km/h than the upcoming M5.

Both new 5 Series M models will be produced in all-wheel drive xDrive configuration for left-hand drive markets only, meaning the uniquely engineered rear-drive right-hand drive M550d models will be about 70kg lighter (and therefore quicker and more efficient) when they hit the UK in October, about four months after the X5/6 M50d.

BMW Australia has confirmed it will release both the X5 M50d and X6 M50d – the latter as part of a range-wide X6 facelift – in the third quarter of this year, but says the M550d sedan and wagon are unlikely to appear here.

“X5 and X6 (M50d models) will arrive in the third quarter, timed together with the facelifted X6,” said BMW Australia spokesman Piers Scott. “And that's it for now. We have no plans for the rear-drive (M550d) sedan or Touring at this stage.”

Apart from unique steering ratios, suspension tunes and in some instances chassis components from their full-M model siblings, all four M diesels will feature subtle interior and exterior styling upgrades over their donor models, including M Sport bumpers, seats, steering wheels and sill plates.

The X5 and X6 super-diesels will cap a busy year for BMW Australia, which will launch the M5 and new 3 Series sedan range just a week apart next month, followed by the M3 Pure Edition in March and, later, new M6 coupe and convertible models.

This year will also bring the all-new 6 Series GranCoupe and upgraded 7 Series limousine, followed in 2013 by the all-new X4 and in 2014 by the ground-breaking new i3 electric hatch and then i8 plug-in hybrid super-coupe.