How to Remove Oil Stains from a Concrete Garage Floor

Concrete is a deceptively porous material that acts like a thirsty sponge for automotive fluids. Once oil seeps into those tiny surface capillaries, it creates a dark, stubborn blemish that resists standard soap and water. Achieving a clean finish requires a balance of chemical breakdown and mechanical abrasion to pull the contaminant out of the substrate. Done well, your garage floor will be free of slick, dark spots and ready for a fresh coating or simply a cleaner appearance. This process is less about brute force and more about letting the cleaning agents dwell long enough to do the heavy lifting before you scrub them away.

1. Absorb the Oil Fast. If the oil is fresh, pour clay-based cat litter or sawdust over the area immediately. Let it sit for at least an hour to soak up as much surface liquid as possible before sweeping it away.
2. Soak It Down. Pour a concentrated concrete degreaser or a strong dish soap solution directly onto the stain. Ensure the entire discolored area is saturated but not pooling excessively.
3. Let Chemistry Work. Cover the treated stain with a plastic sheet or old rag to prevent the degreaser from evaporating too quickly. Let it sit undisturbed for at least 30 to 60 minutes.
4. Agitate the Stain. Using a stiff-bristled nylon or wire brush, scrub the area in a circular motion. Apply firm downward pressure to agitate the pores of the concrete.
5. Blast It Clean. Use a garden hose with a high-pressure nozzle or a pressure washer set to a wide fan pattern to rinse the area. Direct the flow toward the garage door threshold to push the runoff outside.
6. Assess Your Progress. Allow the floor to dry completely. Inspect the area; if a shadow of the stain remains, repeat the process starting from the degreasing step.