The new M550d unveiled with four turbos.
BMW has introduced its second 5 Series M Performance model: the new M550d xDrive, just months after the first M Performance 5 Series arrived in the form of the M550i xDrive. The gas-powered M550i xDrive proved to be rapidly quick, with a claimed 0-60 mph time of 3.9 seconds, and it appears the diesel variant will be equally potent thanks to the addition of an another turbo. The previous M550d utilized a 3.0-liter tri-turbo straight-six. In its latest iteration four turbochargers have been used.
This has helped it become the most powerful six-cylinder diesel engine in the world. The quad-turbo 3.0-liter straight-six makes 395 horsepower at 4,400 rpm – equaling the E39 M5's V8 – and 560 lb-ft of torque from just 2,000 rpm, which is a fair chunk more than the 501 lb-ft generated by the outgoing M5. BMW says 332 lb-ft of that is also available from 1,000 rpm. Two low pressure turbos replace the previous large-sized third turbo and are permanently powered while the car is in motion. A second high-pressure turbo joins the party when the engine exceeds 2,500 rpm.
Power is sent to all four wheels via a M Performance eight-speed automatic, enabling the sedan to hit 62 mph in 4.4 seconds and the wagon (Touring) in 4.6 seconds. That makes it just one-tenth slower than the F10 M5 and 0.3 seconds faster than the previous M550d. Like the M550i, the diesel variant gets an M Sport suspension that drops the body 10 mm closer to the tarmac, an optional adaptive M Suspension Professional featuring Dynamic Damper Control, and an Integral Active Steering (rear-wheel steering) with variable rack-and-pinion ratio. Aesthetic enhancements range from new bumpers and diffuser to blue brake calipers and a boot spoiler for the sedan.
Exclusive 19-inch M wheels come standard with optional 20s finished in Cerium Grey, a color that also trims the kidney grille and door mirrors. The interior comes coated in leather, Alcantara and aluminum, with M-specific steering wheel, pedals and instrument display. The sedan will hit showrooms in July, with the Touring to follow later in the year. Alas, the M550d won't be making it over to North America