Murphy USA in Rockdale (715 W. Us Highway 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.