BMW has released the first teaser video of an all-new diesel-powered M vehicle, believed to be dubbed X6 M50d.

The X6 M50d doesn't have a 5.0-liter engine, but 3.0-liter, inline-six oil-burner. With two turbos, the engine will likely make more than 370 hp and more than 500 lb-ft of torque. It will be the most powerful six-cylinder diesel on the light-duty market by far - Ram's HD pickups use a 6.7-liter diesel inline-six to produce 350 hp and 800 lb-ft - and rumor has it that the turbos will operate in three different stages, making power when you want it, sipping fuel when you don't, and balancing the two when you're feeling greedy.

The diesel will be backed by a ZF eight-speed automatic and standard all-wheel drive. This powertrain also will find its way into an X5 M50d and even an M5 50d. All three will be visually differentiated not only from their lesser diesel siblings, but their gas-powered M counterparts as well.

According to the Car & Driver magazine, the new M models go on sale in Europe by summer 2012. There are no plans to launch them in the U.S.