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Synthetic Vs. Mineral Oil for Car Maintenance

Your odometer is clicking up and up – you can see by the sticker that the lube shop technician left on your windshield that it’s time for your regularly scheduled oil change. Whether you decide to do this job yourself or have it done for you, it’s important for you to know the reasons why or why not to use synthetic oil in your engine.

The most important thing to remember is to know your car. Many people never crack the binding on their service manual. They leave it hidden deep in the belly of their vehicle’s glove compartment. This little book is a virtual “bible” about your vehicle, and you need to take the time to read it from cover to cover. It outlines service schedules for your car, what all the parts are, as well as the type of oil which is recommended for your vehicle.

Oil lubricates all the moving parts of your engine. Different cars will require different oils to keep everything running smoothly. Some will need 10W30, others 5W30, some run on diesel oil. Depending on the age, type, horsepower and machining of your engine, you may or may not need synthetic oil.

Car Maintenance

“Mineral” oil, or oil derived from organic compounds, comes from the ground. It is extracted by various methods and is turned into oil for your vehicle. Mineral oil, as a natural compound, has irregularly sized molecules. Because this is an organic compound, the mineral oil molecules might be close together in one section and far apart in another in the same bottle of oil. This might not sound like a big deal, but it can be, depending on your engine. If the filings in your engine are only the size of a pinprick and the organic oil molecule is as wide across as a straw, then the organic oil molecule just won’t be able to go into your engine. This can cause clumping and inadequate flow of the oil to all the parts of your engine. You’ll be more likely to end up with clogs, and oil that changes viscosity (how fluidly it moves) throughout your engine. You can have blockages appear where you least want or expect them to be. That sometimes results in engine blockages, but more often results in poor fuel mileage, blown cylinders and poor fuel mileage.

The nice thing about synthetic oil is that it is chemically made to have molecules spaced evenly apart all the way through the liquid. So when it expands, it expands evenly throughout the oil. When it cools, the space between the molecules becomes smaller throughout the oil. This results, overall, in a cleaner running car, that produces less pollution and that consumes less gasoline.

Synthetic Vs. Mineral Oil

Sounds great right? Why wouldn’t everyone just go out and purchase synthetic oil then?

Well, for one thing, synthetic oil is expensive. On average, synthetic oil costs at least double what a mineral-based oil does. Whether you choose to do this yourself or to go to a lube shop or your dealer, the cost difference can be a bit tough to swallow. Some also claim that the process of making synthetic oil is not environmentally sound – others state that organically obtained and processed oils are terrible pollutants.

Another consideration is that, for cars that are more than 10 years old especially, unless they have always used synthetic oil, switching to synthetic oil is not necessary. These cars were machined to operate with the original organic mineral oils as opposed to the newer synthetic oils. If you’ve always used the mineral-based oils, changing this late in the game doesn’t do all that much to benefit you, your car or the environment.

No matter what kind of oil you decide to use for your vehicle, remember to dispose of it as environmentally as possible. Ask your auto dealer or lube shop about how they deal with your old oil. And feel good about taking care of your car.