Until recently a BMW ‘M’ car represented the pinnacle of handling, always used a petrol engine and was strictly rear-wheel drive. The X6 M50d uses a diesel engine, sends power to all four wheels and weighs well over two-tonnes. So does it really deserve to wear the M badge?
Firstly, it’s not intended to be a full-fat ‘M’ car, instead its a product of BMW’s new M Performance division (other models include the X5 M50d, M550d and M135i) which aims to offer high-performance models with a slightly softer edge. In that respect, the X6 M50d fits in perfectly.
At its heart is an all-new 3.0-litre six-cylinder tri-turbo diesel engine producing 376bhp and a phenomenol 740Nm of torque. The pioneering layout, the first of its kind in the world, uses two small turbos and a third much larger turbo to maximise power across a wide power band. Because the small turbos spin up easily they provide the lag-free throttle response, while the larger unit takes over higher in the rev-range.
It works brilliantly, too. Throttle response is razor sharp and the huge surge of torque starts earlier and finishes later in the rev range. As with all BMW’s six-cylinder diesels it also sounds fantastic, so letting it rev is rewarded with a burbling crescendo from the exhausts.
Adaptive air suspension, self levelling at the rear, comes as standard, but get’s M-specific tweaks to the springs and dampers. Despite these firmer settings, and 20-inch alloys as standard, it rides well and body control is astonishing. Drive quickly down a narrow twisting road and you soon forget how large the X6 is, until a car appears coming in the opposite direction, that is.
The X6 M50d is a brute of a car that cements BMW’s position at the top of the engineering tree, but with other cheaper and almost as accomplished diesels in the X6 range it’s destined to be a rare sight on UK roads.