A news release from Case IH explains that the use of biodiesel blends, and in some cases B100, is now approved in the majority of their products.
The B5 approvals first announced in 2004 were just a starting point. Following proper maintenance and fuel requirements, use of 20 percent biodiesel blends (B20) are approved in more than 90 percent of the models now being sold in Europe and North America, including the workhorse Magnum tractors. And, nearly half of the models sold globally, including the flagship Axial-Flow 8010 combine are approved, following proper protocols, for 100 percent biodiesel (B100). Your local Case IH dealer will soon have details on specific technical requirements for use.
See the news release for full details. Further biodiesel information is provided here. The moral of the story appears to be consult your dealer before filling up with more concentrated biodiesel blends.