Fuel wator separator filter???

[Chamberpains]

Oh, I'll have to add that using high concentrations of biodiesel will also run you through a filter ultra-fast. Sometimes under a thousand miles.

This was kind of disappointing to me because I had a documented slight MPG gain from using biodiesel before I changed from a 50 micron filter to a 10 micron. Oh well, I'd sooner save the fuel system then save money on fuel.