In Indiana (and the OP is from Indiana), "Rickers" gas stations have their own card and it's tied to your checking account. It works for both Gas and Diesel, and get 5 cents off a gallon, except on Mondays when you get 10 cents off a gallon, either gas or diesel. Plus you get points when you use it in the stores when purchasing items, and things like... 5 donughts and the 6th one is free, or 5 cups of coffee the 6th is free type stuff.
However, "Rickers" is not nation wide and the card is good only at a "Rickers" station. Still, I get my fuel at Rickers (locally), and just cringe when traveling having to stop at other stations for fuel.
Might be good to explore a card that has a wider range.