BMW X6 M50d 2012 Review

What we liked:
>> Planet-turning diesel grunt
>> Standard three-seat rear bench
>> Physics-defying handling dynamics

Not so much:
>> Oddball SUV-coupe shape
>> Extensive and expensive options list
>> Inconsistent hot-weather performance

OVERVIEW
>> World’s most powerful diesel six arrives Down Under
BMW’s high-riding X6 ‘SUV-coupe’ has been a hit globally, exceeding expectations by attracting about 150,000 sales – as well as spurring it develop the upcoming 3 Series-based X4 and Audi to develop its forthcoming Q6 – but the Bavarian brand’s most controversial model has not achieved the same success here.

BMW Australia hopes an extensive midlife makeover, the local debut of the world’s most powerful volume-produced six-cylinder diesel passenger car engine and the addition of a three-position rear bench seat as standard will rectify that.

The new X6 M50d’s new tri-turbo diesel engine slams out no less than 280kW of power and 740Nm of torque, and the same outrageous new oil-burner also powers BMW’s new X5 M50d which goes on sale here in two months. Between them, the first two M Performance Automobiles models to arrive in Australia have already attracted more than 70 Australian buyers.

PRICE AND EQUIPMENT
>> Price and spec up across the board
Pricing for the upgraded X6 is up by $1000 across the range, while the range-topping X6 M is $5500 more expensive than before at $190,900 plus on-road costs.

Opening the freshened range at $110,900 is the turbo-diesel xDrive 30d, while the trubo-petrol xDrive 35i is next up at $121,000. Then there’s the twin-turbo diesel $127,400 xDrive 40d and the V8 petrol-powered xDrive 50i at $150,400.

Priced less than $7000 higher at a neat $157,000 – some $33,900 less than the range-topping twin-turbo petrol V8-powered X6 M – the new X6 M50d costs precisely $10,000 more than the new X5 M50d ($147,000 - $11,200 less than the X5 M), despite the latter’s ability to carry more cargo and up to seven passengers.

All facelifted E72-series X6s come with a new front bumper with redesigned kidney grille and higher/wider foglights, new L-shaped tail-lights and the option of adaptive LED headlights ($3400), while the M50d comes standard with the US market X6 hybrid’s ‘Powerdome’ bonnet, which costs $1100 extra on all other models.

The usual host of BMW options is available across the range, including metallic paint ($2000), an electric glass sunroof ($3500), a selection of 19- and 20-inch alloy wheels costing up to $4800, self-levelling suspension including rear air suspension ($2200 – standard on 50i and M50d), steering wheel heating ($500), an alarm ($1050), auto soft-close doors ($900), four-zone climate-control ($3200), an active driver’s seat ($900), front seat ventilation ($1500), lane departure warning system ($1400), active cruise control ($4700), rear DVD system ($4400), TV ($2800) and anthracite headlining ($700).

Specific M equipment for the M50d includes an aggressive bodykit that swaps front foglights for massive air intakes, M Servotronic steering, M-tuned Adaptive drive active rollbars, M-tuned front springs and dampers, revised eleastokinematics, 20-inch 435 M-style double-spoke alloys with 315/35 R20 run-flat tyres, BMW Individual High-Gloss Shadow Line exterior trim, an M gearshifter, Ferric Grey wing mirror caps, a pair of black twin oval exhaust outlets on either side, M door sills, Aluminium Shadow Brushed interior trim, Nappa alcantara/leather trim with M badging, a 16-speaker 600-Watt surround sound system.   

Three new exterior paint colours are available for the 2012 X6 - Glacier silver, Midnight blue and Marakesh brown – along with two new upholsteries: Ivory Nappa and Vermillion red.

BMW Australia has sold around 1900 examples of the X6 since 2008, but expects the facelifted model – including the new M50d – and the addition of a standard three-seat rear bench seat (previously a $700 option) and internet access ($200) to increase sales.

MECHANICAL
>> Tri-turbo diesel is latest X6’s wildest party trick
There are no mechanical changes for the midlife X6 makeover, except for the addition of the tri-turbo diesel engine in the M50d, which also represents BMW Australia’s first model in the new M Performance range – BMW’s answer to Audi’s S-prefixed model family.

Based on the single-turbo 3.0-litre inline six-cylinder N57 diesel engine fitted across the BMW range (and the twin-turbo engine in the 535d and X6 40d), the M50d features a large, low-pressure turbo bookended by two smaller, high-pressure turbos, the first of which force feeds the engine alone at up to 1700rpm, before feeding the large turbo in the midrange, and the second of which continues to spool up all the way the engine’s high 5250rpm cut-out.

The result is no less than 280kW at 4000-4400rpm and some 740Nm of torque at 2000-3000rpm, claimed 0-100km/h acceleration in a sportscar-like 5.3 seconds and official combined fuel consumption of just 7.7L/100km.

The same engine in the all-wheel drive M550d all, which is not produced in right-hand drive guise and therefore remains unavailable in Australia, is capable of hitting 100km/h in a staggering 4.7 seconds – the same as the previous E60 M5 V10 super sedan and just four-tenths slower than the latest twin-turbo V8 petrol-powered M5.

At the other end of the X6 range - which comes with an eight-speed auto as standard in all models - is the xDrive 30d, powered by a 180kW/540Nm 3.0-litre turbo-diesel inline six. It consumes 7.4L/100km and accelerates to 100km/h in 7.5 seconds.

Next up is the xDrive35i, which is powered by a 225kW/400Nm 3.0-litre petrol engine, consumes 10.1L/100km and sprints to 100km/h in 6.7 seconds.

There is also the xDrive 40d, powered by a 225kW/600Nm twin-turbo diesel six that consumes 7.5L/100km and propels the X6 to 100km/h in 6.5 seconds, and the 300kW/600Nm 4.4-litre twin-turbo petrol V8-powered xDrive 50i, which consumes 12.5L/100km and can hit 100km/h in 5.4 seconds – one-tenth slower than the M50d, which in turn is six-tenths slower than the X6 M.

PACKAGING
>> Five seats is not all the 2150kg X6 now offers
Chief addition for the upgraded X6 range is a three-seat rear bench, in place of the twin rear bucket arrangement of the original model it replaces.

BMW says almost all Australian X6 buyers previously opted for the three-seat second row, making its standard fitment a no-brainer for the upgraded range.

It also defends criticism that despite weighing 2150kg, the original X6 accommodated just four occupants and just 570 litres of luggage (extending to 1450 litres with the rear seats folded) on the basis that it still swallows more than a Volkswagen Touareg.

COMPETITORS
>> X6 is pretty much unique, until the Audi Q6 arrives
BMW says it created the ‘Sports Activity Coupe’ category with the X6, which as such continues to have no direct competitors. However, its closest rivals are probably Porsche’s sportiest Cayenne, the naturally aspirated V8 GTS (a new version of which has just been launched in Europe) and the V8 Range Rover Sport line-up, which opens at $139,900 and closes at $179,500.

Of course, Audi’s ballistic 4.2 and 6.0-litre diesel-powered Q7s are natural rivals for the M50d, and while the Q7 6.0 TDI ($257,700) out-powers the tri-turbo diesel X6 with a 386kW/1000Nm diesel V12, its 5.5-second 0-100km/h time falls short. The 250kW/760Nm Q7 4.2 TDI ($129,300), meantime, is in another league with 0-100km/h acceleration in 6.4 seconds.

ON THE ROAD
>> Forget the marketing spin and savour the technology
We’ll be honest from the outset and say we’ve never liked the X6. It might have attracted 150,000 buyers around the world -- mainly Americans, Russians and Middle Easterners -- but large numbers of Australians are yet to be convinced by a high-riding four-door ‘coupe’ that accommodates just four people, is difficult to see out the back of and carries less luggage than the X5, which attracts 10 times as many customers here.

Indeed, the last thing our warming planet needs is a 2150kg luxury SUV that’s unlikely to leave the bitumen much, but exists for a privileged few who are happy to trade cargo space for stand-out styling and want the flexibility of a high ride height and all-wheel drive to reach their occasional country weekender.

The new-look X6 range changes none of that, except for the addition of a three-pew rear bench seat as standard, which at least allows it to transport five people, and BMW continues to point out that its fastback-style rear-end still swallows more luggage than a Touareg and that not all premium SUV buyers want the boot space of an X5. Fair enough.

Truer to BMW form than the controversial X6 is the inaugural M Performance model’s bahnstorming tri-turbo diesel engine, which is a technical tour de force that easily lives up to its reputation as the world’s most potent six-cylinder diesel passenger car (non-truck, tractor, ship or train) engine.

Despite displacing just three litres, the triple-turbo oiler not only delivers effortless, lag-free diesel torque right from idle and a beefy dose of V8-belittling midrange grunt, but continues to slam out neck-straining torque until the rev-limiter spoils the fun at about 5250rpm, which is sky-high for a diesel.

Combined with a slick-shifting eight-speed auto, which can be paddle-shifted up or down through multiple ratios without the slightest transmission snatch, the M50d engine is more like a petrol engine in the way it piles on the revs so willingly, delivering its massive reserves of torque so effectively to the road that the ‘M-lite’ X6 is capable of hitting obscene speeds before you know it.

The only reservation we have concerns its hot-weather suitability, with that big dose of top-end urge all but disappearing above 4000rpm after being pushed hard for repeated laps in near-30 degree heat at Darwin’s Hidden Valley circuit during the national media launch.

Once rested, the same X6 M50d performed as impressively as before and never missed another beat, allowing us to revel in what is one of the finest diesel engines we’ve ever sampled. No, its raw outputs are not as lofty as the 6.0-litre V12 TDI in the Q7, but the heavier Audi doesn’t match this BMW’s commendable efficiency or physics-defying acceleration – despite displacing double the capacity.

The other deficiency the Hidden Valley session revealed was brake fade, but that’s understandable for a two-plus-tonne SUV driven in anger for half a hour on a racetrack, where the brake fluid and pads in most production cars can be fried within a few hard laps.

On the flip-side, the X6 M50d continued its gravity-defeating performance in the area of dynamics, by sitting flatter and tracking more faithfully on the track than any SUV this size or weight has a right to.

Yes, there was a touch of steering kick under hard braking over the ripple strips and the X6 couldn’t hide its bulk during aggressive corner entries, when the outside front tyre loaded up then activated the DSC system with surprising ease – unless I nailed the apex with inch-perfect precision then unwound the steering lock under a modulated throttle pedal while pointing to the outside of the track.

Such is the torque of this tri-turbo diesel that ham-fisted full-throttle manoeuvres from low speed on anything but a straight, dry surface will light up the DSC warning light like a fire cracker – despite the super-effective xDrive all-wheel drive system that can send up to 100 per cent of engine power to either end of the vehicle, and distributes torque across its rear axle not by braking the inside wheel, but by directing more power to the outside wheel.

No, we still don’t like the X6, but the M50d engine is a masterclass in diesel engineering that should find a far more practical home in the X5 within a month or so. Better still, if only BMW would produce the all-wheel drive M550d sedan in right-hand drive, then Australians would have access to what is the first diesel M5 by another name.

Read the latest Carsales Network news and reviews on your mobile, iPhone or PDA at the carsales mobile site