Want an indication of just how quickly gas mileage is improving?

Consider the 2011 BMW 335d. BMW's last diesel 3-Series model achieved a respectable 36 mpg on the highway and an unimpressive 23 mpg city, for a combined 27 mpg figure.

The 2014 BMW 328d's gas mileage figures have just been revealed on the EPA's fueleconomy.gov website (via Autoblog), and it's as much as 10 mpg better over every metric--recording 32 mpg city and an excellent 45 mpg highway, for a combined 37 mpg rating.

That's better even than the current diesel economy champ, Volkswagen's 2013 Passat TDI. The Passat is rated at 35 mpg combined, reaching 43 highway and 31 city.

The 328d does so by giving away a liter of capacity and two cylinders to the old BMW diesel, and its 180-hp and 280 lb-ft ratings do lag the 335d's mighty 265 horsepower and 425 lb-ft torque numbers.

But the 328d is still no slouch--badged 320d in Europe, the same engine delivers a 0-62 mph time of just 7.4 seconds and 142 mph at the top end. Slower than the old car, but quick enough to deal with most daily duties without breaking a sweat.

328d buyers get a sole transmission choice, BMW's excellent eight-speed automatic, while xDrive all-wheel drive and an xDrive wagon option will also join the range later this year.

xDrive models are marginally less economical, with figures of 31 mpg city, 43 highway and 35 combined. The wagon could prove a very useful vehicle, combining identical economy figures to the xDrive sedan with a 17.5 cu-ft load space.

The 2014 BMW 328d sedan is expected to hit dealerships this fall, priced from $39,525 for the regular, rear-drive sedan. xDrive models are predictably a little extra, starting at $41,525, while the xDrive Sports Wagon is priced from $43,875.


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