BMW M550d xDrive 2012 Review - International

BMW M550d xDrive

OVERVIEW

This is like no diesel in history, though, with three turbo-chargers, a cylinder head bolted directly to the main bearing cover and 280kW of power.

It’s got torque to burn, with 740Nm at 2000rpm, and it’s got speed to burn, too, whipping through to 100km/h in 4.7 seconds on its way to its 250km/h limiter. Remove this (as M Performance Automobiles surely will for the optimistic), and the M550d xDrive will run into the mid-290km/h range.

But don’t think this is another rear-drive, twin-turbo M5 rival. BMW is smarter than that. It’s a whole different animal, thanks in part to all-wheel drive, an eight-speed automatic transmission and an astonishing 6.3-litre/100km combined fuel economy figure.

It’s a car (and a sub brand) built to bridge the gap between the standard BMW range and the stonking M cars, and that’s exactly what it does.

And it’s well equipped for the money. Besides all-wheel drive, a six-step chassis/character adjustment switch, the widescreen MMI setup and the big motor, the M550d xDrive gets a full M leather interior.

That includes a new sports seat that’s not quite M5 and much grippier than the 535d seat and a fat, leather steering wheel with its own gearshift paddles.

It’s visually subtle, too, with a deeper front splitter that gives the car most of its extra length and two enormous air intakes on either side. It runs aggressive looking 20-inch wheels and tyres, a subtle rear spoiler lip, trapezoidal tailpipes and a host of other M Performance Automobiles touches that you’d swear are straight from the M options list.

There are other standard features that work, like Xenon lights, four-zone climate control, adaptive cruise and, naturally, electric seats.

It might be called M Performance Automobiles but it’s still BMW so, of course, there is an option list. And it’s extensive…

But that’s not the bad news. The bad news is that Australia won’t be getting this car. Ever.

We might end up with its mighty, beating heart somewhere, somehow (probably in the X5 version), but the M550d xDrive’s all-wheel drive system isn’t geared up for right-hand drive work.

Bugger.

It revs to 5400rpm, but delivers its 280kW power peak at 4000 (and holds it to 4400). It’s torque peak, meanwhile, turns up at 2000rpm, thanks largely to the first two of the in-line, 3.0-litre six-cylinder engine’s three turbo chargers. That’s right. Three.

With two small turbochargers and one large one (with variable geometry), the M Performance Automobiles range delivers both terrific light-throttle turbo response and top-end grunt.

The 2993cc engine’s smallest, lightest turbo-charger starts whizzing just above idle and the second one chimes in at 1500rpm to instantly deliver the maximum torque figure (which it holds until 3000rpm). The biggest of the turbos is locked out until 2700rpm, crams in air until the engine’s delivering 280kW of power from 4000-4400rpm, then remains on station as the motor spins out to a petrol-esque 5400rpm.

It attaches this to its eight-speed automatic transmission unit, tweaked to suit the M badge’s more sporting pretensions, and this splits its drive between all four wheels through the xDrive system.

To cope with all of this, they’ve stiffened the chassis, the suspension, the springs and dampers and, even though it weighs 1970kg, that’s only 25kg more than the M5, even though it’s toting all-wheel drive.

You better believe that if the body styling didn’t get wild and woolly with the M5, it’s not going to be wild on the M550d xDrive, either.

Instead, what it gets is an identical set of interior dimensions, including the boot.

The differences to the bodywork are largely a reflection of the cooling and air mining BMW needed for the tri-turbo setup, including an enlarged front air intake with a huge front splitter and a pair of smaller intakes on either side of it.

Its bonnet is identical to the standard 5-Series unit but the boot carries a small lip spoiler, with a flat diffuser underneath it, in between its trapezoidal exhaust tips.

It has bigger wheels and tyres, too, including standard 245/40 R19 tyres, though most will plump for the optional 20-inch boots.

It scores an M-coded gearshift lever, an M steering wheel with shift paddles and M550d markings on the kicker plate, just in case you forget.

There are electric sports seats, too, along with four-zone climate controlled air conditioning, radar cruise control and a host of other luxuries.

A full complement of airbags is matched by a complicated array of electronic driver aids, three-point inertia reel seatbelts with pyrotechnic pretensioners and force limiters at the front and anti-whiplash head restraints in all five seating positions (there’s that number again).

The high-strength body utilises a combination of aluminium, high-tensile, and ultra-high-tensile steels around “precisely defined zones” which include its load-bearing structures, rigid passenger cell and crash deformation paths. Optional safety equipment includes Lane Change and Lane Departure warning systems, and BMW’s Night Vision technology.

BMW has been careful so that the M550d xDrive doesn’t step on any BMW toes, so you can rule that out. The big V8 diesel market in Europe has been shrinking for years, so there aren’t many of those anymore.

The trick with this car is that it’s so good, it will attract traditional petrol buyers as well as diesel buyers.

BMW has delved into every trick in the bag with this one, from tightening down on the cylinder heads to fine tuning the exhaust and even synthesizing the best of the engine’s sound through the audio system.

It’s hard to complain with the results. It’s superb. It has leapt from nowhere to one of the best engines in the world today.

You can build up the revs to over 2000rpm, step off the brake pedal and hang on as the tri-turbo launches its host to 62mph in 4.7 seconds. And then keeps going.

It doesn’t exactly feel like it explodes. It’s more like it grabs the road by the scruff of the neck and starts turning the world around it. It’s blisteringly quick, but it never descends into brutality and it sounds charmingly sonorous without ever even hinting at coarseness.

One of the tricks to that is the synthesizing of the engine’s note and pumping it back through the car’s terrific audio system to concentrate the sound. It’s a trick to counteract the sound deadening effect of three successive turbo-chargers and if you weren’t aware of it, you’d never know it was happening.

It’s an engine rich in character from idle to 5400rpm, with a deep rumble that rises in urgency along with your throttle opening.

And, Lordy, is it fast. It’s fast at any throttle opening, in any gear, at any time.

It’s a lovely combination in the drivetrain and the car’s multi-mode drive system, which ranges from EcoPro, Comfort, Sport, Sport+, Manual and Customized, makes a notable difference.

In keeping with the straddling nature of the M Performance Automobiles brand, the Comfort setting is firmer than the standard 5-Series but softer than the M5. All of the settings make optimized tweaks to the suspension, throttle response, gearshift software, skid control systems and steering.

In its EcoPro mode, it’s capable of astonishing feats of economy, clocking just 6.3 litres/100km on the combined cycle (a full 3.6 litres or better than the M5). In Sport+ mode, with its skid control gear switched off, it fires to its top speed of 250km/h with a willingness that belies its mass.

Yes, it’s an astonishingly strong motor and it is willing to attack hard, to surge smoothly or to cruise gently, depending on your mood. And, yes, it dominates the machine, but it’s not the only trick in the book.

The real charm is that it works so coherently with everything else. It retains the 5-Series chassis balance that has made it well regarded even in its initial year of sales.

It is unfailingly secure in the way it handles and it’s almost impossible to upset it in tight corners, long sweepers or on mid-corner bumps. Even with the skid control switched off, the M550d just takes the engine’s power and drives it into whatever tyre can employ it. Just like that, no fuss.

The transmission is another beautifully thought-through component, sliding through gears seamlessly unless it’s in Sport, when it bangs the changes through to reinforce the M-Lite’s sportier nature.

In fact, the only minor issue is the electric steering, which masks the last few percent of interaction with the machine beneath you.

Other than that, it’s hard to imagine how BMW could have made this car better. Except, obviously, the addition of right-hand drive…

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