There’s a distant chug at idle, and mid-range acceleration sounds industrial, but the top end’s timbre is powerful and relatively tuneful. Motorway cruising is as hushed as you’d want. The big 20in wheels yield some road noise, and thump over urban pocks, but you’ll hear the impact more than feel it.
At speed, imperfections bring front-end shudders with the Adaptive Drive dampers in either normal or sport mode, but the anti-roll function is excellent. In league with the accurate, reasonably feelsome steering, it allows uncanny dartiness.
The retuned eight-speed auto ’box is well mapped and decisive, though Sport mode keeps revs so high the noise becomes wearing. Positive-feeling override paddles let you trouble the 5800rpm red line.
Traction off the line is excellent, and continues that way. Only the blinking traction aid light and eager ABS remind you how much work the gizmos are doing to separate you from the physics in play.
Should I buy one?
Adaptive Drive isn’t available on the £49,340 40d, though the M50d’s exterior and interior addenda can be approximated by a £1965 Dynamic Package.
The M50d’s special alcantara and leather seats are handsome, supportive and grippy, and self-levelling rear suspension and an X6 M-style bonnet bulge further differentiate from the 40d. Heated seats (£305) and sat nav (£1925) are the M50d’s main shortcomings against the six-speed-only, £85,710 X6 M’s kit, but the former’s price and economy advantages easily outweigh such shortfalls if you’re prepared to trade power for torque.
BMW X6 M50d
Price £62,260; Top speed: 155mph (limited); 0-62mph: 5.3sec; Economy: 36.7mpg (combined); CO2: 204g/km; Kerb weight: 2225kg; Engine type, cc: 6 cyls, 2993cc, turbodiesel; Power: 376bhp at 4000-4400rpm; Torque: 546lb ft at 2000-3000rpm; Gearbox: 8-spd auto