In standard guise, the BMW X5 and especially its controversial X6 sibling are already very rapid and surprisingly agile, questioning not only the necessity of an M-division variant but also whether it was even possible to improve their performance.
It seems subtlety is not part of the M-division vocabulary, engineering its new X5 M and X6 M flagship models to extraordinary heights, beginning with the engine.
Under the bonnet sits a deceptively familiar twin-turbocharged 4.4-litre V8 engine, although BMW has fettled with its components to extract a staggering 408kW – which is 108kW more than in the standard xDrive50i – and maximum torque of 680Nm produced virtually across the entire rev range from 1,500 and 5,650rpm.
Needless to say, this has had a dramatic effect on straight line performance, accelerating from zero to 100km/h in just 4.7 seconds with the help of Launch Control, and an electronically limited top speed of 275km/h.
This new M TwinPower Turbo engine is also the first in the world to use a common exhaust manifold joining both rows of cylinders, with the turbochargers and catalytic converters positioned in the V-section, ensuring the spontaneous and direct response.
While fuel consumption is by no means frugal, it still remains quite impressive for a vehicle of this size and performance, using just 13.9 litres per 100km and emissions of 325 grams per kilometre.
This engine is mated as standard to a six-speed M Sports Automatic transmission with the driver able to manually select gears from either the shift lever or aluminium shift paddles on the steering wheel.
As the first all-wheel-drive models built by BMW M GmbH, a combination of BMW xDrive and Dynamic Performance Control delivers a level of agility unparalleled in this segment with outstanding driving dynamics combined with supreme driving stability and excellent traction.
Both the BMW X5 M and the BMW X6 M come as standard with air suspension and self-levelling on the rear axle as well as Adaptive Drive with electronically adjustable dampers (EDC) and active anti-roll control.
A double-track control arm arrangement on the front axle coupled with newly developed three-way support mounts give both the suspension and dampers a particularly sensitive response, with either Normal or Sports damper settings as well as the Servotronic steering control map chosen with the EDC or the M Drive button.
The high-performance brake system guarantees supreme stopping power and high resistance to fading under all conditions. The brakes come with four-piston fixed callipers at the front and swing callipers at the rear, combined in each case with inner-vented lightweight brake discs.
Along with the less-than-subtle M-division exterior treatment, the X5 M and X6 M also feature Bi-xenon dual headlights including a daytime driving light function, adaptive brake lights and 20-inch light-alloy rims as standard.
The interior of the X5 M and the X6 M comes with electronically adjustable M sports seats, dual-zone automatic air conditioning, the BMW Individual instrument panel with leather padding, Merino leather covering additional surfaces and trim features, M entry trim and footrest, interior highlights in brushed Aluminium Shadow, as well as automatic operation of the tailgate on the BMW X6 M.