How to Remove Stubborn Oil Stains from Garage Concrete

Concrete acts like a hard, gray sponge when it comes to motor oil. Because concrete is porous, oil doesn't just sit on the surface; it wicks deep into the capillaries of the slab, making a simple wipe-down ineffective. If you leave the stain too long, the oil bonds with the mineral structure of the concrete, which is why those dark, greasy patches seem impossible to budge. Getting a floor truly clean requires a multi-stage approach of extraction followed by emulsification. You aren't just washing the top layer; you are pulling the oil out of the pores and breaking down the remaining residue so it can be rinsed away. Done well, the garage floor should lose that dark, shadowed look and return to a uniform, clean gray.

1. Soak Up the Spill Fast. If the oil is fresh, pour cat litter or sawdust over the puddle to soak up as much surface liquid as possible. Let it sit for at least an hour before sweeping it up and disposing of it properly.
2. Saturate the Stain. Spray a high-strength, water-based concrete degreaser directly onto the stained area. Saturate the concrete fully so the liquid can penetrate the pores.
3. Work It Deep. Using a stiff-bristle nylon brush, scrub the degreaser into the concrete using circular motions. Apply firm downward pressure to work the cleaner deep into the pitted areas.
4. Let Chemistry Do the Work. Allow the degreaser to sit on the stain for 15 to 20 minutes, but do not let it dry completely. If it starts to dry, mist it lightly with a spray bottle of water.
5. Flush Everything Away. Use a high-pressure hose nozzle to rinse the area clean, pushing the emulsified oil toward the garage drain or the driveway edge. Ensure all chemical residue is washed away.
6. Draw Out the Deep Stain. For stains that have been there for months, mix a thick paste of baking soda and degreaser. Spread it over the stain, cover with plastic, and let it sit for 24 hours to draw the oil up to the surface.