Add Yahoo as a preferred source to see more of our stories on Google. Green pump for diesel, blue for gas – but what's the difference? Jeffrey Greenberg/Education Images/Universal Images Group via ...

Not all diesel is created equal. Like gasoline, it comes in various grades, and choosing the right one is important. But which should you pick?

In our day and age, automakers and governments alike work together to find more sustainable fuel sources. Well, some governments - and automakers - only care when they make a profit off caring ...