I Pull Into the Left Lane of the Autobahn near the Austrian border and put my foot down at about 80 mph (120 km/h). The U.S.-spec BMW 335d sedan churns, roars and lunges like a runaway locomotive, quickly hurtling to the electronic speed limiter at about 135 mph (217 km/h). The cars in front scamper to the right lane like frightened animals.

Settled in the passing lane, the cabin quickly becomes hushed, with only a faint thrum emanating from the engine bay. For a few glorious kilometers, I am the undisputed king of the road, loping down the autobahn at a ridiculous speed in the most fuel-efficient vehicle BMW AG ever has offered for sale in the U.S.

Maybe the auto industry's fuel economy binge won't be so boring after all.

More than 20 new diesel cars and trucks will arrive in the U.S. during the next two years, but if any vehicle can change America's mind about compression-ignition engines, this is the one.

Preliminary average Environmental Protection Agency numbers are 23/36 mpg (10/6.5 L/100 km). Yet the car sprints to 60 mph (97 km/h) in six seconds flat, thanks to BMW's 3.0L twin-turbo inline 6-cyl. that makes 265 hp and a pavement-wrinkling 425 lb.-ft. (576 Nm) of torque in U.S. dress.

The new selective catalyst reduction emissions control system for the U.S. creates some backpressure that lowers output by 13 hp but does not affect torque.

The engine also is remarkably light, featuring an aluminium block. Most diesels have blocks made of much heavier cast iron or compacted graphite iron. Add iron to the robust design required for compression-ignition engines and you usually get a nose-heavy vehicle that corners like it has a snowplow attached.

But the 335d has the same sharp reflexes as a gasoline-powered 3-Series. In fact, its nearly perfect 51/49 front-to-back weight-distribution ratio allows it to corner as well as any 3-Series.

It is a little less entertaining to manually wind the 335d through the gears than its twin-turbo gasoline-powered sibling, but the additional 125 lb.-ft. (170 Nm) of torque creates its own special, more relaxed driving pleasure on challenging, twisty roads that would have you endlessly upshifting and downshifting with a gasoline engine.

BMW has sold sporty diesels in Europe since 1983, and 71% of all BMWs currently sold in Europe have diesels.

Aside from the hassle of hunting for a diesel pump (in the U.S.), there are no compromises with this high-mileage car, especially when you can go almost 600 miles (967 km) between fillups.

Another benefit: It is likely that — unlike hybrid-electric vehicles — the 335d's real-world fuel-economy numbers will exceed the EPA's.

After about 180 miles (290 km) of flogging, the trip computer reports average fuel consumption of nearly 28 mpg (8.4 L/100 km) and the 16 gallon (61 L) tank still is more than half full.

Diesel fuel prices now are coming down, edging closer to premium unleaded, which is the usual fuel for BMWs anyway, so the high cost of diesel fuel is not the issue it was a few months ago. And most fuel experts say diesel fuel prices should settle down in the U.S. for the foreseeable future.

To meet 50-state emissions rules in the U.S., the 335d uses a selective catalyst reduction emissions system it calls BluePerformance to neutralize smog-causing oxides of nitrogen by injecting urea (labeled AdBlue) into the exhaust stream.

To introduce SCR, which also will be required soon in Europe to meet upcoming Euro6 standards, BMW has developed an active and passive 2-tank system it says improves customer convenience.

Urea is injected from the active tank containing about 1.6 gallons (6 L) by means of a dosage pump.

The active tank and dosage pipes also are heated because the urea solution freezes at 12 degrees F (-11 C).

The active tank is connected to a second passive tank that holds 4.5 gallons (17 L). Overall, engineers say a full load of urea adds about 50 lbs. (23 kg) to the vehicle's weight.

Having this much urea on board means the system only has to be replenished during regular oil-change intervals, usually about every 13,000 miles (21,000 km).

Under normal conditions, the customer will never have to bother with additional service, Wolfgang Mattes, BMW's head of U.S. diesel research and development says, adding the cost of refilling the tanks is covered under BMW's no-charge maintenance program for the first four years or 50,000 miles (80,000 km).

Mattes says the system will require early replenishment only under extremely aggressive driving. In that case, a warning light comes on about 1,500 miles (2,400 km) before the fluid runs out.

If the driver ignores the warning, only about five starts will be allowed once the fluid gets within 200 miles (322 km) of running dry, Mattes says, but he emphasizes it is highly unlikely a typical BMW owner will ever face such a scenario.

Pricing will not be announced until closer to launch in December.

Light Trucks to Dominate New U.S. Diesel Growth
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[+]PROS/CONS[-]
Huge torque Fuel still expensive
36 mpg hwy Finding fuel not easy
Perfect weight balance Complex emissions control

'09 BMW 335d

Vehicle type: front-engine, rear-wheel-drive, 5-passenger sedan

Engine: 3.0L turbocharged I-6 diesel; aluminum block/aluminum head

Power: 265 hp @ 4,220 rpm

Torque: 425 lb.-ft (576 Nm) @ 1,750 rpm

Compression ratio: 16.5:1

Transmission: 6-speed automatic

Wheelbase: 108.7 ins. (276 cm)

Curb weight: 3,825 lbs. (1735 kg)

Base price (est): low $40,000

Fuel economy: 23/36 mpg (10/6.5 L/100/km)

Competition: Lexus GS450 h