Choosing the Right Motor Oil

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Making sure to use the correct engine oil for your car is easy. Check out these tips.
When it comes to auto maintenance, checking your engine oil and choosing the right motor oil are both easy things to figure out. The first step is to simply pull out your handy owner's manual and check to see which oil weight (viscosity) is suggested for your vehicle by the manufacturer.
The automaker spends enormous amounts of time and money to design and create the motor for your car and they know best when it comes to which motor oil will do the best job for your specific make and model of car. Go by their sage advice on which oil is best for your engine. The right oil gives you optimal performance and keeps your motor running longer and stronger.
In your owner's manual you'll find the correct specifications, certifications, and viscosity of oil to use. But what do these terms mean? Let's find out.

What is Viscosity

Oil viscosity is all about how thick the oil is. The thinner the oil viscosity, the quicker it flows through your engine and the thicker the viscosity, the slower it flows. Higher oil viscosity is represented by higher numbers on the label of your oil container. The higher the viscosity, the more resistant the oil is to flow through the motor.
If you use a viscosity that is too high, it will make your engine sluggish and unresponsive. Because it is thicker it takes more energy in the form of fuel for your motor to overcome the resistance of the oil and get where it needs to go. Today's engines are built to tighter tolerances and require lighter viscosity oil. For instance, an oil that is rated 0W-40 is better for fuel efficiency.
Types of Motor Oil
The first thing you need to identify when looking for motor oil is whether it is designed for diesel or gasoline engines. No, you can't use the same oil for both. You find the correct motor oil by looking on the round grade label. If you see an "S" that indicates the oil is for gasoline-powered engines. If you see a "C" on the label, that means the oil is meant for diesel-powered vehicles.

These days, motor oil comes in various forms to best serve your particular car. Again, check your owner's manual for the type of oil for your vehicle. Here's what you need to know about conventional, semi-synthetic, and full synthetic motor oil.
Conventional mineral oil is generally used in older engines. It has a low resistance to oxidation and heat and is good for from 3,000 to 5,000 miles of use. If you've always used mineral oil in your car, keep using it. Its thick structure will help keep your engine from producing leaks.

Full synthetic oil has a much higher resistance to heat and oxidation than conventional motor oil. You can easily travel 6,000 miles before needing to change your synthetic oil. You'll change your oil less frequently than with conventional oil but synthetic oil costs more. According to a survey by the American Automobile Association's (AAA) Approved Auto Repair facilities reveals that the average cost of a conventional oil change is $38, while a synthetic oil change is $70. For those that change their vehicle's oil themselves, the average cost of five quarts of conventional oil is approximately $28, while synthetic oil is $45.
Synthetic oil has superior anti-friction properties than conventional oil and is known for being more slippery. Full synthetic oil offers the best engine responsiveness and fuel economy. It is great for city driving where you have a lot of stop and go traffic and periods of idling. It also helps to extend the life of your engine.
Semi-synthetic oil is a blend of both conventional mineral and synthetic oils, giving you the benefits of both. Semi-synthetic oils defend your motor against higher temperatures and accept heavier loads than conventional oil. The low friction and viscosity characteristics of semi-synthetic oil improves fuel economy and is not subject to evaporation as are conventional mineral oils.

Oil Grade

The oil's viscosity is indicated on the label as its grade. For modern cars, the most-used motor oil is marked as 5W-20. The 5 indicates the cold viscosity of the oil, the W stands for Winter, and the 20 indicates the engine's running temperature or hot viscosity. Your owner's manual will inform you on the suggested motor oil grade that is best to use in your car. The best-selling motor oils today are 5W-30 and 5W-20. The higher the number, the thicker the oil, relating to the oil's operating temperature. The average car's internal engine temperature is 212 degrees Fahrenheit.
Motor oil grades are a scale developed by the Society of Automotive Engineers (SAE) to describe the viscosity of oil. The terms "grade," "viscosity," and "weight" all describe the thickness of the oil. That's why you often hear an SAE30 oil described as "30-weight."
What your Motor Oil does
Your motor oil provides lubrication to the internal engine parts, lessens friction of engine components during the combustion cycle, thus reducing wear and tear. During the combustion process, fuel and other lubricants oxidize and create acids and your motor oil helps to neutralize those acids. Additives in motor oil keep the engine block clean and free of sludge and harmful residue that can block the engine if not properly removed. The oil also prevents corrosion and rust inside the cylinder blocks.
OEM Specs
Not all brands of motor oil give you the same level of certifications. You want to use engine oil that follows the specifications of your car's manufacturer. Only use reputable and tested brands of motor oil. You want an oil that is formulated to meet or exceed industry standards. That's where certifications come in.
Your motor oil should surpass the criteria of such automaker groups as the American Petroleum Institute (API), the Association of Certified European Automakers (ACEA), and the International Lubricant Standardization and Approval Committee (ILSAC).
Keep it Clean
So, now that we have convinced you about how important your motor oil is, the best way to maintain your vehicle is to have the oil and oil filter changed at regular intervals as described and outlined in your owner's manual. Your local Lithia Auto dealer has ASE-trained and certified technicians on hand to service your vehicle every 3,000 miles to keep your engine running smoothly for many happy miles of motoring. You'll find your local Lithia Auto dealership here.