This subject comes up frequently and it's funny to hear people talking about getting .03 cents off at Flying J with a card that changes every month on how you have to use it. That's $1.50 on a 50 gallon purchase, just enough to buy a candy bar. If you get the PenFed card you get 5%, that's five percent off of every purchase. On a 50 gallon fill up, that's a $7.50 savings, enough for lunch. Between our cars and RV, we usually see about $375.00 in savings a year.
Now if you stay away from Flying J and quit paying for the size of their lot, you can get another .08-.10 cents a gallon off by buying at the station across the street. Now that's another $5.00 on a fill up. Now you can get your wife a little something for lunch too!