With any manner of liquid spill or stain, the golden rule seems to be that “if you catch it early, its easier to clean,” and motor oil is no different. The less time it’s had to soak itself into your driveway or garage, the better.
First, use something to absorb as much of the puddle as possible. We recommend baking soda with a cup of fine grain kitty litter or sand, or oil absorbent pads. Either way, uses these to cover the motor oil. After a minimum of two hours (we recommend leaving this overnight) the motor oil and litter/sand/baking soda mixture should be visually darker or the pads should look as if they physically absorbed liquid motor oil. Confiscate these used materials into a separate garbage bag or the like. Take them to somewhere that offers motor oil disposal in your area (check with you local mechanic, as they may offer it or know of the appropriate venue). Do not simply throw it away, as it is potentially hazardous materials.
Once this is finished, rinse any remaining puddles away with a garden hose. Then, dab at the area with a rag or old t-shirt. For any remaining spots, pour about a half cup of laundry detergent or hydrocarbon mitigation agent over the spots and let it sit for 5 – 10 minutes, allowing it to get into the stained areas and attack the motor oil.
Afterwards, gently scrub the area with a wire brush using a circular motion, occasionally dipping the brush in a small bucket of warm water. After about 5 minutes, rinse the area with your garden hose again. Using another rag or old t-shirt, blot the stained area. If the stain remains once the area is dry, try repeating the process.
Photo courtesy of chelle.