if your truck is newer than a 94 then you have nothing to worry about if its older then you have to change the lines because biodiesel will eventually eat thru the old rubber lines . my trucks fuel system is completyl stock i had to make no modifications to run biodiesel if anything you will have to change your fuel lines but thats it nothing else would have to be done . i'm not sure but i think a 94 is ok and needs nothing but if i were you i would double check on it