19 July 2012 by Tim Bowdler, Deputy Editor

  • Triple-turbo X6 will do 0-62mph in 5.3s
  • Massive 740Nm of torque, with 375bhp
  • 40% tax payer will pay £698 a month

When BMW first launched its X6 coupe/4x4 crossover in 2008 it was greeted with both enthusiasm and derision: its schizophrenic design splitting opinion.

Some regarded it ugly – probably the same people who decreed that the Porsche Cayenne was no looker – and others dismissed it as unnecessary. Still, four years on and it’s still here with a refresh, albeit one that’s barely noticeable.

What is noticeable, however, is the inclusion of the new M50d Performance - the first diesel model from the company’s M performance division - into the X6 line-up.

This is not to be confused with a straight M model, or the M Sport model. This version straddles the two and the tag ‘Performance’ points to its key attribute which is a six-cylinder 375bhp triple-turbo 3.0-litre engine with a monster peak torque figure of 740Nm. That, for the record, is the most powerful diesel ever to come from BMW.

Now 740Nm is a monumentally large slab of pulling power and because there’s three turbochargers that muscular acceleration is spread right across the rev range. That translates to a 0-62mph sprint of just 5.3 seconds achieved smoothly and effortlessly, particularly with the slick-shifting eight-speed auto. The M50d M Performance also uses a high-tech four-wheel-drive system that balances the right amount of power between the front and rear wheels to maximise traction. It is fantastic to drive, blending seamless acceleration with grippy, dependable handling.

All this means you get a fantastic road-holding in a high performance car that, with an average claimed fuel economy of 36.7mpg isn't too shabby. If you are thinking of getting one as a company car, it's not a great idea - with CO2 emissions of 204g/km and a resultant Benefit-in-Kind tax rating of 34% a 40% tax payer will have to shell out a fairly shocking £698 a month.

In terms of its looks, the X6 isn’t what you’d call subtle. A blunt-nosed 4x4 with a sloping rear, it’s something of centaur, but this model does get 20-inch alloys and an oversized front air intake to differentiate it from the lesser models in the range. It also gets BMW’s Adaptive Drive system as standard to make it more agile than the cheaper X6s.

Although it’s got a smooth power delivery and decent handling characteristics, the ride is a little firm which means it can get choppy on poorly surfaced roads and those oversized 20-inch alloys don’t help. They also generate quite a bit of road noise too.

It’s not particularly practical either because the sloping roof compromises bootspace and headroom at the rear. You can fold the rear seats fold down for extra load capacity but if you are regularly carrying kids for weekend trips, you’ll probably go for the X5.

The interior is of top quality, and it’s reasonably well kitted out with leather upholstery, parking sensors, dual-zone climate control as standard but you’ll have to shell out extra for sat-nav which seems a little stingy for what is a £62k car.

For the full BMW X6 review click here.

Also consider:

Porsche Cayenne
This diesel model with 245bhp isn't as fast as the M50d but it is markedly cheaper and a good all-round package.

Mercedes-Benz ML63 AMG
An ML with bells on, the petrol-engined 63 AMG will get to 62mph from a standstill in 4.6 seconds. It's a no-compromise brute.

VW Touareg 4.2 V8 TDI Altitude 5d Tip Auto
This big old bus has a 0-62mph sprint time of 5.6 seconds, and is also much more roomy than the BMW.