Biodiesel is usually sold blended with petrodiesel and is designated B?? where ?? is the percentage of biodiesel. B5 would be 5% biodiesel and 95% petrodiesel. B20 would be 20/80% and of course B100 would be pure biodiesel. Most manufacturers do not recommend above B5 and threaten to void the warranty if higher percentage are used. Truck fleet owners have had success with B20 and some even report lower maintenance costs with B20 than pure petrodiesel. If you want to play it safe than you should stick with whatever manufacturer recommendations (usually B5).
2010+ engine models already have engine emission control systems that make them compatible for using biodiesel. As a matter of fact; Biodiesel already passed the national fuel standards.Try Feece oil for an assured quality of biodiesel fuel. Here is a link to their site http://funadvice.com/r/15o7dotul23