I have done alot of reading and research on converting vegetable oil into useable fuel oil and personally I wouldn't put straight VO in my truck! VO contains glycerin. Glycerin is a humectant, not to mention it can get real gummy. What's that mean? A humectant attracts moisture, that's why glycerin is used in skin products. But I think even more important is the gumming up of everything from you fuel intake tube to the injection nozzles would really suck!


http://journeytoforever.org/biodiesel_mike.html

has some great info on making your own. It's not too difficult and you can get the oil for free from restaurants in the area! Ingredients are basic, methanol, lye and oil.