Motor oil lubricates engine components and cuts down on friction. Friction causes increased heat (which increases wear) and the engine parts to slow down. Motor oil creates a small barrier of film between the parts in order for them to slide past one another. The slippery portion of parts increases effieciency, power and performance. Another important thing to remember is that properly lubricated parts uses less fuel than one that isn’t properly lubricated. Have you ever had your vehicle fail a smog inspection just because your engine’s oil was dirty? It can happen. If an engine is not running efficiently, it causes more fuel contamminates to enter your oil which will cause it to fail smog as it will emit those contaminates into the air.
One more piece to this puzzle to consider is when your car’s engine isn’t running. How can this happen, you ask? When your car’s engine is turned off, the oil drips off the engine. This is where the majority of engine wear comes from start up. Less lubricant on the engine, more friction and more friction equals more wear. Oil also abosorbs the particulates of the engine wear which is filtered by the engines oil filter. As the oil breaks down due to fuel contamination or engine wear, it will develop slug and slug will enter into the engine components causing premature wear. So not only is the oil in need of changing, so does the oil filter. They both play a key role in keeping your engine free of grit.
So by changing your engines oil at the required oil changes, you help reduce the friction, allow the engine to run efficiently which in turn saves you money.
Oil Grades, which one is right for your car’s engine?
Good question. The main differences in engine oil is their viscosity grades. Don’t let the word overwhelm you, is is really quite simple. Viscosity is a measurement of how quickly the oil flows through your engine. Since thicker viscosity oils take longer to flow, it makes sense that an oil with a higher viscosity grade would run more slowly through your engine components. This means that SAE 30 moves faster than SAE 60, for example.
Oils with a higher viscosity provides more lubrication and a greater lever of protection to your engine. The downside is that these oils also take longer to initially cover the engine components after vehicle start up. And remember, start up will cause greater wear on your engine than the general running of the engine.
Now, oil with a lower viscosity provides a quicker flow of oil to cover the engine components, which minimizing the amount of dry running. However, lower viscosity oils provide less lubrication during normal running of the engine.
So what should you do, protect your engine at start up or protect your engine while running? Good question. Do not worry, it does not have to be either or. Oils react differently in different temperatures. These oils have two numbers listed on the bottle. You have probably seen 5W-30 or 10W-40? These are examples of these types of oils.
Anytime you see a number with a W, it represents how the oil will react in colder temperatures (when the engine is just turning over versus when it has been running for a while). As you can see, it has a very low W rating, or viscosity grade. that allows a quick flow of oil when the vehicle is first started. This coats the engine components quickly so there is less dry rubbing between parts. Then as the engine oil temperature increases it becomes thicker and in turn allows for more lubrication.
The moral to this article is, changing your engines oil not only prolongs the life your cars engine, but it also keeps more cash in your wallet. Be sure to check your manufactures recommended oil grade in your owners manual and how often it should be changed. Future articles will cover Oil Additive ratings and Synthetic Engine Oils, are they right for your car’s engine?