The Basics of Engine Oil: Keeping Your Engine Happy
Few things are more important in a moving vehicle than the engine oil. Because a car relies on moving metal against metal to work, the only way to keep the vehicle running smoothly without rubbing itself apart is to lubricate the moving parts. This is one of the main jobs of engine oil. Without this lubrication layer, the parts of an engine cannot work smoothly and avoid the friction that can cause the engine to overheat. This oil requires regular replacement in order to stay free enough of impurities to continue to do its job. The numbers on a bottle of oil provide important information for choosing a certain kind of oil.
Weight or Viscosity
The viscosity, or oil weight, is the thickness of the oil. This is often 5 weight or 10 weight. Thinner oil moves less quickly but coats metal more thoroughly. If you are a baker, it is similar to the way shortening vs. olive oil can be used to spread things on a pan. The best oil is able to straddle between flowing smoothly through the system yet coating thoroughly. More modern oils have a multiple number, like 10W 30 that shows the weight at a certain temperature. The reason for this designation is that there are added polymers to allow different viscosities at different temperatures.
Synthetic vs. Regular Oil
Synthetic oil is designed to keep from breaking down in the system and is considered more stable. It is less likely to break down its components at extreme high and low temperatures due to chemical reactions that can be stimulated by the temperature change. It is also believed to coat metal surfaces more effectively than standard oil, causing less sludge from metal wear. Because of this, oil changes are needed less frequently than with conventional oils. Synthetic oil is more expensive than conventional engine oils, and as it is a newer product, there are some skeptics who still question its superiority.
After a certain amount of time, it is necessary to change oil. Oil needs to be replaced because it picks up grime from the small amount of wear that occurs in the engine. Though oil is a lubricant that is meant to prevent wear, it cannot completely protect an engine from all wear. Components in the oil can break down at very high or low temperatures or take on small amounts of water, which break down its effectiveness. For conventional oil, changes are usually recommended every 3,000 to 5,000 miles. Synthetic oil can be changed every 10,000 miles. Some newer cars can go a longer time between oil changes. It is best for a vehicle owner to check the manufacturer’s recommendations to be certain.