July 29, 2014

A Complete Guide to Oil Changes for Your Used Car

A Complete Guide to Oil Changes for Your Used Car

Regular maintenance is one of the most important things you can do for your car. Keeping a regular maintenance schedule will make your car last longer and run better. And at the core of any regular car maintenance routine is the simple oil change. But if you’ve never owned a car before, or if you don’t keep up with maintenance like you should, you need to know why oil changes are important and when and how they should be done.

What Engine Oil Does

To many car buyers, the engine systems underneath the hood are a mystery best left to the professionals. But in truth, engines and other mechanical systems are mostly simple and easy to understand. This is especially true for oil changes and how they help your car.

Every gasoline engine has parts that move and turn. This includes the pistons inside your engine, the shafts that take the force from the pistons and use them to spin the wheels, and the gears and cranks that join the larger parts together. However, running an engine also creates large amounts of heat and friction. The primary function of engine oil is to reduce the friction between pieces of the engine so it runs smoothly and without wearing down.

However, engine oil has other functions as well. It helps keep your engine clean by filtering out soot and unburned fuel that enters the engine case. It can prevent engine parts from rusting, and it also uses detergents and other additives to clean parts as they move through the oil. Some oils include zinc, which forms a protective coating on engine parts. In the end, then, oil performs many vital functions in your engine, and your car can’t run without it.

Choosing the Right Oil for Your Car

When you take your car in for an oil change, the technicians at the shop will usually ask you a few questions. They may ask you what oil weight you want, if you want conventional or synthetic oil, and if you want any additional additives along with it. Understanding all these concepts can take a while, but here’s a short guide to the most important points.

The first thing you’ll see when you’re looking at different oil types, other than the brand name, is a number-letter combination such as 10W-30 or 20W-50. These numbers refer to the viscosity of the oil, or how thick it is inside the engine at a certain temperature. The first number shows the minimum temperature, and the second the maximum. Keep in mind that the numbers are not temperatures themselves, but references to a temperature scale.

Put more simply, oil rated at 5W-30 will be relatively thin and less viscous, which lets it work in colder temperatures. Oil rated at 20W-50 is thicker and heavier, so it works well in higher temperatures or with more pressure.

So how do you choose which oil to put in your engine? The best way is to see what your manufacturer recommends. In almost every car’s owner’s manual, the carmaker gives recommendations on what oil to use in the engine under normal use. Some people opt to use other oils, but for the most part these recommendations work fine.

Another thing to consider is whether you want synthetic or conventional oil. Conventional oil is made from crude oil pulled from the ground, while synthetic oil is a blend of artificial chemicals. In general, synthetic oil lasts longer and offers more protection for your engine, but it’s also more expensive. It’s your choice which one you want to use, but you can always consult your manual or ask a technician at your dealership for advice.

Checking and Changing Your Oil

Once you’ve chosen an oil for your car, you should check it regularly to make sure your car has enough. This is a relatively simple process that is the same for almost every car. You’ll simply want to pull onto a level surface, open your hood, and pull out the dipstick (which is connected to a brightly-colored handle somewhere near your engine). For the best results, clean the dipstick with a rag and dip it back into the engine before reading it. Your manufacturer may also recommend waiting until your engine is cool before checking the oil, but this isn’t always the case.

If your oil is between the lower and upper marks on the dipstick, you’re good to go! If not, find your oil reservoir (usually a screw-off cap on the top of your engine) and add a quart of your chosen oil.

What about oil changes? Many people still go by the old “3 month or 3,000 mile” rule for an oil change, but in truth this is probably too much for most modern cars. Many car companies specify longer service intervals for newer models, such as every 6 months or 5,000 miles under regular driving conditions. Check your owner’s manual to see what your manufacturer recommends.

Of course, none of this advice is useful if you don’t have a car to practice it on. If you’re looking for a great deal on a used car in Oklahoma City, come to The KEY (Oklahoma’s best buy here pay here dealership) today! We have OKC’s best selection of late-model used cars, and we can finance your purchase even if you have bad credit or no credit at all! You can even get approved online and find your perfect car from the comfort of your home, then come down to the dealership and pick it up. Follow us on Facebook or Google+ for more information and special deals.


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