Exxon in Thorndale (201 E US-79)

This tends to be the cheapest gas station in Rockdale, it is right outside of Walmart. They generally stay clean. Occasionally you can get a good deal and get a few dollars off of gas by purchasing items "inside." However, if you aren't trying to save money on gas, their car maintenance items: windshield washer fluid, oil, etc. are the same items available in Walmart next door, but marked up considerably.