Tar is difficult to remove and can destroy the aesthetic appeal of your vehicle. But first, where does tar come from? Tar is an oil-based substance that is mixed with different construction materials. Meaning, it will stick to your vehicle unless you do something about it. Its oily texture allows it to stick and accumulate on various parts of your vehicle exterior, especially on the lower region. This can happen due to a number of reasons – driving on newly constructed road, hitting potholes, off-road driving, etc.