Diesel passenger cars have long been the domain of German carmakers, but that will change early next year with the launch of the 2014 Chevrolet Cruze diesel four-door compact sedan.

The eagerly awaited model, the first GM (NYSE:GM) passenger-car diesel since the early 1980s, was confirmed more than a year ago by CEO Dan Akerson.

We now have a few more details of the diesel Chevy Cruze, courtesy of a chat with Jim Federico, GM's vehicle line executive for compact, small, mini and electric vehicles.

2013 launch as 2014 model

The diesel Cruze will be launched in the first half of next year, as a 2014 model. It will have a short model life, as the entire Cruze line will be redesigned and updated in 2015.

Given the engineering work required to certify the European diesel engine for sale in North America, though, the new 2015 Cruze will likely continue the diesel version, probably from launch.

Federico told us that the 2.0-liter direct-injected turbodiesel engine to be fitted to the Cruze Diesel will be equipped with the AdBlue urea emission control system, making it compliant with present and future emissions regulations.

That system injects a small amount of vaporized liquid urea and water solution into an exhaust gas aftertreatment catalyst to convert nitrous oxides into nitrogen and water.

2013 Chevrolet Cruze

2013 Chevrolet Cruze

A similar system is used on larger diesel vehicles sold in the U.S., including diesel versions of the Audi Q7, BMW X5, and Mercedes-Benz GL Class and ML Class. So far, it's not used on Volkswagen's Golf TDI and Jetta TDI.

Federico said the urea tank will be refilled at every oil change, at intervals of 10,000 miles or perhaps longer (the company is still working on the final specifications).

No output ratings are yet available for the Federalized 2.0-liter diesel; in Europe, it's rated at 161 horsepower and 266 lb-ft of torque.

Lots of work on noise suppression

Federico told us that the biggest challenge for the Cruze diesel has been noise suppression.

European buyers, Federico said candidly, tolerate more engine and mechanical noise than do U.S. buyers.

With the gasoline Chevrolet Cruze being one of the quietest compacts on the road at highway speeds, the bar for noise suppression is set high for the diesel team.

How to label a diesel?

A new variant of a car that already delivers 33 mpg combined in its Cruze Eco six-speed manual version (or 31 mpg combined for the automatic version), the diesel Cruze hasn't yet been given a model name.

In Europe, it's known as the Cruze 2.0 VCDi, but somehow we suspect it'll get a different name here.

With "Eco" being Chevy's designation for the highest-mileage versions of its passenger cars, we expect Chevy to choose a diesel sub-brand--rather as Chrysler has selected "EcoDiesel" as the label for its upcoming 2014 Jeep Grand Cherokee diesel.

Chevy said in February, though, that it will be "difficult to discern" any difference on the outside between diesel and gasoline versions of the Cruze.

Chevrolet Cruze 2.0 VCDi turbodiesel (Europe)

Chevrolet Cruze 2.0 VCDi turbodiesel (Europe)

Fuel efficiency: TBD

The crucial question, of course, is what kind of mileage the diesel Cruze will deliver in the real world. Drivers of VW Jetta TDI diesels report real-world mileage higher than EPA ratings for their cars.

If the Cruze diesel follows suit--we expect it to carry EPA fuel efficiency ratings higher than the Cruze Eco--than it's possible the car might deliver close to 40 mpg in real-world use.

Engineering of the North American diesel Cruze is being done jointly by engine designers in Pontiac, Michigan; vehicle engineers in Russelsheim, Germany; and GM diesel specialists in Torino, Italy.

All Cruze diesels will be built on the main Cruze assembly line at GM's Lordstown, Ohio.

+++++++++++

Follow GreenCarReports on Facebook and Twitter.