HERNDON, VA - Hoping to quash memories of 1970's-era diesel clatter with social media marketing, Audi has launched a pro-diesel campaign complete with viral video and a Facebook Cause.

Coinciding with the launch of the Q7 TDI SUV, Audi launched an online video called "Truth in Diesel" that aims to build an emotional bond with potential car buyers. You can build your bond after the jump.

"You get behind a cause, you don't get behind an engine option or a feature," Audi America Marketing boss Scott Keogh told the Wall Street Journal.

For those who are already behind a cause, the automaker completed a successful partnership with the Nature Conservancy. Every time someone supported its Facebook Cause, the non-profit got a dollar from Audi for carbon offset programs.

Audi's "diesels are sweet" campaign follows Volkswagen's effort to make diesels lovable with the "TDI Truth or Dare" blog, which aims to debunk common misconceptions people have about the engines and the fuel. "Many Americans still don't understand the benefits clean diesel provides," Keogh said in a statement. "That's why Audi developed an intensive campaign to spread the truth about TDI technology."

Boring old facts aren't enough to sway Americans who associate diesel with greasy hands, sooty VW Rabbits and idling tractor trailers - and that's where Facebook comes in. According to the Journal, ad agency Factory Design Labs is working on a Facebook game described as "Mob Wars meets Oregon Trail."

For its part in winning over the hearts and minds of diesel detractors, the "Truth in Diesel" video starts with footage of 1970s-era oil crises and touts the environmental and foreign policy benefits of clean diesel. It's a companion piece to the "Di*sel: It's No Longer A Dirty Word" television campaign (shown above) that shows oil barrels rolling back onto a ship in order to represent the 1.5 million barrels of foreign oil the US could avoid using if a third of drivers switched to diesel. Of course, the ad is on YouTube.

Audi also set a goal to recruit enough supporters through Facebook at $1 each to reach $25,000. They did, and in less time than Audi, Facebook, or The Nature Conservancy expected it would take.

Audi's $25,000 donation supports the first voluntary carbon offset program, to help reforest and restore the Tensas River Basin in Mississippi. The program helps counter-balance carbon emissions by planting trees on private lands to capture and store carbon, an also help restore habitats that are critical to local animal species.

Visit www.EcoTraveller.info for news on where to go green when you drive green.