BMW today announced pricing and fuel efficiency of its first new 50-state legal clean diesel vehicles that are going on sale shortly. The new 335d sedan is rated at 23/36 mpg city/highway and will be priced from $44,725 while the X5 xDrive35d will get a 19/26 mpg rating with a $52,025 base price.

The European version of the Mazda6 is now available with a new 2.2L four cylinder turbodiesel engine that provides increased performance compared to the company's older 2.0L diesel while retaining similar fuel consumption and CO2 emissions. The new MZR-CD 2.2 is also the first to be equipped with Mazda's newly developed particulate filter that has increased intervals between regeneration cycles for longer life and lower fuel consumption.

Boasting a leg up on the German and French competition, Hyundai Motor Co. has introduced its new diesel "R-Engine" in 2.2L and 2.0L variants for markets outside North America. The 2.0L diesel engine is rated at 184hp and 289 pound-ft of torque, while the 2.2L reaches 200hp and 321 pound-ft torque.

Despite the massive juggernaut of TDI and the logistics machinery to support a two-week drive, Audi spent the last two weeks seeding the market with the Audi Mileage Marathon in somewhat guerrilla or viral fashion. Given the word-of-mouth nature of interest for diesels, it may be the right marketing approach considering the anxious buying public and so far niche-nature of diesel buyers.

The longest single stretch of the Audi Mileage Marathon is now over as the fleet of diesel vehicles rolled into Denver Colorado at the mid-point of the event. The diesel fleet is still showing impressive mileage numbers even through the more challenging conditions encountered on the circuitous route from Chicago to Denver.  The Q7s and Q5s in particular are demonstrating impressive efficiency for their segments.

Audi's first big promotion for its upcoming diesel vehicles is starting today in Manhattan as the Audi Mileage Marathon leaves from the Tavern on the Green. For the next two weeks, a fleet of 23 diesel powered Audi cars and SUVs will visit cities all across the country as four waves of journalists from all over the world explore the capabilities of these vehicles. The participants will be vying for the best mileage on each of the four legs of the journey.

California, with the strictest emissions standards in the nation is the driving force behind the new emissions rules and that's where Green Fuels Forecast spent a day driving the new diesel Jetta. Volkswagen has devised a machine that lives up to the brand's fun reputation while still delivering exceptional fuel efficiency.

Renault reveals a diesel hybrid crossover concept vehicle that will be publicly shown for the first time at the Paris Motor Show in October. The Ondelios is a six passenger crossover claimed to deliver 52.3 mpg (US).

Mazda announces it will introduce a new clean diesel engine for the European Market at the upcoming Paris Motor Show. The engine features a new Mazda-developed diesel particulate filter that reduces the regeneration time and fuel consumption.

German automaker Audi is preparing to make a major push for the launch of its clean diesels in the US market with a cross-country Mileage Marathon in October. A fleet of 23 TDI powered Audis including the Q7, Q5, A4 and A3 will go from New York to Los Angeles with the drivers vying for the best possible fuel economy.