If you're looking for a few simple answers to these questions, then the National Biodiesel Board would like you to download a new PDF called "Biodiesel Myths Busted." The brochure includes helpful items like this one:
Myth: Biodiesel use voids manufacturers' engine warranty coverage.
Fact: All major U.S. automakers and engine manufacturers accept the use of up to at least B5, and many major engine companies have stated formally that the use of high quality biodiesel blends up to B20 will not void their parts and workmanship warranties. For a listing of specific statements from the engine companies, please visit the National Biodiesel Board Web site.
The PDF also covers issues of biodiesel's shelf life, whether there is a biodiesel fuel standard, how it operates in cold weather and its effect on food prices. Get it here.
[Source: National Biodiesel Board]