actually, train transport is becoming increasingly GREEN...my friend works as an engineer. They're slowly planning a huge take-over of the trucking business. So your biodiesel might be greener than you thought Jeremy5848!

As for the mutated fuel filter, I'm no expert, but I do run a van on grease. All I can say is that the warning I hear time and time again when you run on grease is to make sure you have the right hoses as the veggie oil can corrode some cheaper hoses and fuel line parts.

Hope it helps.