The familiar sedan you see here is the most fuel-efficient BMW sold in the United States since the 13-hp Isetta of the late 1950s. And before you look at the specs, where you might expect to see some yawn-inducing straight-line performance numbers, we should point out that the 335d will whup the first- and second-generation M3s in a stoplight drag race. In fact, the 335d nearly keeps up with the muscle-car 335i, a twin-turbo bully of a 3-series that gives the current M3-V-8 and all-a run for its money.
The switch to the "d" in the suffix of the newest 3-series' name explains why it can travel almost 40 percent farther on a gallon of fuel-d stands for diesel. Just like the 335i, the newest 3-series uses a 3.0-liter, aluminum-block in-line six with piezo direct injection and two turbochargers. The 335d is available exclusively with a six-speed automatic-none of the manual transmissions in BMW's arsenal can cope with the diesel's massive 425 lb-ft of torque.
It's doubtful that the lack of a clutch pedal will cost BMW many sales, as the 335d's ZF-supplied gearbox is beautifully calibrated to work with the diesel powerplant. Its shifts-whether multiple-gear, rev-matched downshifts or flat-to-the-floor upshifts-are nearly imperceptible and perfectly timed. Concerns about missing out on the symphony of sound created by BMW's gasoline engines are nixed after one run up the tach scale-the 335d sings the same hollow and haunting straight-six song that long has made the 3-series a favorite for fans of the music of combustion. There's an overlay of diesel clatter below about 2500 rpm, but because BMW has remained faithful to the balanced in-line six engine layout, none of it translates to harshness. No, from just off idle to its redline, this diesel engine is damn near as smooth, rewarding, and quick as its gasoline counterpart.
In fact, the only place where the 335i feels quicker is in the first few feet off the line. Despite using one teensy turbocharger and one larger one to diminish lag (in place of the 335i's identical twin turbos), the 335d is a bit hesitant to get going from a stop. Once moving, though, the engine's computers perform a constant dance, routing intake and exhaust gases to either (or both) of the turbos to minimize lag and maximize output. As a driver, you're aware of none of it-the 335d's massive thrust is simply always at your disposal.