This is a university study of four commercial additives (Power Service, Howe's, FPPF, Amsoil) on D2 and several % of biodiesel blends. It verifies significant improvements to the cold filter plug point (CFPP) using these additives. Which can be the difference between your car operating or not in cold climates. We had a forum member recently have an issue with cold weather (
http://www.e90post.com/forums/showthread.php?p=15084078)
http://www.glmri.org/downloads/2009Reports/pope.pdf