A model is also added to the lineup with the 635d badge. The key there is the final "d" signifying a diesel engine, in this case the 3.0L twin-turbo inline-6. The torquey oil burner will move the two-ton coupe from 0-100km/h (0-62mph) in 6.3 seconds on its way to a top end of 155mph. In spite of this strong acceleration, the 635d will get a combined mileage rating of 34mpg. Just think of what it could do if BMW adds the Two-Mode hybrid system to this diesel.