I am lucky to have a biodiesel supplier about 5 miles from my house. But with the increased price (.30) more a gallon and the cold weather I am only running b-5. I buy 5 -10 gallons of b-100 at a time in 5 gal. jugs and mix accordingly. with my 33 gallon tank 1.65 gal. of b-100 makes b-5! the truck definetly runs smoother and quieter but I have seen no diff. in mileage, but Im sure the higher cetane and lub. properties is going to benifit me in the long run!