Apart from BMW’s Euro-spec 750d and X5 M50d (which have the same engine as the M550d), the only other current production car with quad turbos ... that’s “station wagon” in Continent ...

But the wagon's utility can ... A Brian Tooley Racing Turbo Stage II cam and PAC valvesprings replaced the stock components. The car's existing dual-quad setup was replaced with a single-plane ...

As enticing as a quad-turbo diesel 5 Series sounds (especially in wagon form), a BMW rep confirmed to us that the M550d xDrive will not be coming to the U.S. Again, sometimes life just isn't fair.

BMW has concocted a recipe that will have many car enthusiasts salivating: a diesel-powered, nearly 400-hp, all-wheel-drive, quad-turbocharged 5-series that is available as a wagon. It’s called ...

Created to bridge the gap between the normal 5-Series and the all-out M5, the M550d had a triple-turbo diesel inline-six that made gobs of torque. It was even offered in a wagon body style!