Diesel has been seeing downturn on its luck in recent years. But thanks to a diesel powertrain, BMW‘s latest ‘M’ badged 5-Series model—the M550d xDrive—is as big on power as it is on responsibility, so much so that it could help rehabilitate the fuel’s reputation. Although the company’s ‘M’ division is now spreading its wings and adding flourishes of motorsport technology or styling to a host of BMW models, rather than simply concentrating on making pure, undiluted ‘M’ variants of each production car, a BMW with the M badge on its rear, is never a marketing gimmick.

So, for the M550d xDrive to earn the right to wear the M badge, it has to offer something a bit special, regardless of what type of fuel it runs on. And here, the car doesn’t disappoint as owners will be able to claim their car has the most powerful six-cylinder diesel ever fitted to a production automobile.

It has three liters of displacement, four turbochargers and 400hp. As for torque, a diesel engine’s trump card, there’s 760Nm on offer and it is accessible from 2,000rpm. It may come with an electronically restricted 250km/h (155mph) top speed, but on the way to that figure it will hit 100km/h in just 4.4 seconds. Plump for the bulkier, heavier Touring (station wagon) version and it will still manage that dash in 4.6 seconds.

But M cars have to be fun in the bends as well as on the straight so the M550d xDrive comes with intelligent all-wheel drive, sharper suspension, an eight-speed sports transmission and a ride height dropped by 10 milimetres for improved centre of gravity.

Diesel may have a dirty name at the moment, but in the short term at least, the fuel’s efficiency is going to be crucial in helping truly global car companies meet tighter emissions and economy standards.

It’s why Mercedes invested over €3 billion developing its latest generation ultra-efficient, lightweight OM 654 diesel powertrain that debuted in its E-Class in mid-2016. It’s also why Bentley, a company founded on very torque-y gasoline V8 engines and laterally W12 twin turbo blocks has finally started offering its most fuel-thirsty car—the Bentayga SUV— with a diesel option.

The M550d xDrive has a gasoline sibling, the M550i. It has a 4.4 liter V8 calling the shots and it’s 0.4 seconds faster off the line, has 62 more horsepower but just 650NM torque. It offers a combined fuel economy of 8.9l/100km and 204g/km in terms of CO2 emissions. The M550d returns 5.9l/100km on the combined cycle and 154g/km of CO2.

For more information, do visit BMW.