What is engine oil and what does it do?
Car engine oil is derived from the crude oil extracted by oil rigs, but it goes through a few processes to become the final product you put in your car.
The oil has to be refined into something with a lower viscosity – meaning it's much thinner and smoother – to help the engine turn over more easily and ensure that the oil can circulate quickly around the engine when you start up. It also contains additives to help clean and reduce wear and tear on internal components.
Engine oil is the lifeblood of your car. In certain sections of your engine, the oil creates a layer between the moving parts that helps to prevent friction. Too much friction means the components will wear down faster, causing expensive damage to your car. That’s why it's incredibly important to make sure your car has enough oil. If you do let your car run out of oil, then you run the risk of engine overheating, damage to expensive components, and eventually complete engine destruction.
Why does it run out?
Thanks to the extreme heat and pressures inside car engines, oil degrades over time and becomes less able to protect your engine, so you'd eventually be left with no oil left in your engine at all if you didn't top up regularly. If your car is reaching a ripe old age, then the seals and gaskets may not be as tight as they once were, letting small amounts of oil leak out too.
IMPORTANT: if your car is leaving puddles of oil on your driveway or you have to top up every few weeks, visit a mechanic as soon as possible, as oil leaks can lead to bigger, more expensive problems as time progresses. Pop into a Halfords garage or book an appointment.