With U.S.-market diesels nixed at Audi and on borrowed time over at Mercedes-Benz, BMW stands to be the only German luxury-brand willing to keep selling them here. And BMW’s latest diesel-burner, the 2018 540d xDrive sedan, is shaping up to be a stunner, with huge helpings of the the torque and fuel economy that give diesel-powered entries their appeal. 
For starters, the new 540d’s turbocharged 3.0-liter inline-six?which hails from BMW?s new B57 modular engine family?makes 261 horsepower and a massive 457 pound-feet of torque. (Last year, we drove a Euro-spec 530d, which uses the same powertrain but has a different name.) That?s quite a bit more than the 255 horsepower and 413 pound-feet produced by the old N57-family engine, which powers the X5 xDrive35d and was under the previous-generation diesel 5-series’ hood.
With BMW?s claim that the 540d runs to 60 mph in 5.1 seconds?a half-second quicker than the last 2014 535d we tested?the 540d likely will be the brand’s quickest-ever diesel car sold here. In fact, it might be among the quickest regular-production diesels sold in America yet.
Even so, the diesel 5er sips fuel like a Toyota Corolla?at least on the highway. The EPA’s highway fuel economy estimates for the 540d xDrive land at a solid 36 mpg. The city figure is a respectable 26 mpg, which is more than offset by the stellar highway efficiency to earn the 540d a 30-mpg combined estimate.

BMW Sticking with Diesels in the United...