Car Engine Oil is one of the fundamental products needed to run the car, as it lubricates the engine to prevent the pistons seizing or exploding. As such, the primary purpose of engine oils is to lubricate these moving components including the various mechanisms that are responsible for their activities to help eliminate friction. And you already know that whenever friction is involved, heat is also present. . Engine oil is one of the main lubricants that have a big part to play in the combustion cycle. Car Engine Oil keeps the engine cool and makes sure that the piston rings in the engine are sealed properly.