Before anyone seals it, they will wash the oil and grease stains with a detergent, or a special compound specifically designed to lift oil and grease stains. Therefore, you may want to try this yourself, prior to hiring someone to seal your driveway. The jury is out on the acrylic versus coal tar sealers. Arguably the acrylic sealers are more resistant to grease and oil stains, and the material is considered nonhazardous. On the other hand, coal tar or products containing petroleum distillates have a longer track record, but are considered hazardous to work with, or dispose of. Be aware that many driveway sealers may be latex based but may still contain petroleum distillates or coal tar. Therefore, unlike paints, latex based driveway sealers may be hazardous. Please read the label.