Why Does My Car Need An Oil Change?

We have all been told that we “need” to get an oil change every 3,000 to 5,000 miles or when we reach the number of miles conveniently printed on our windshield sticker. But, most of us are not sure why doing so is important or what will happen if this task is left undone. In a previous post, we discussed which oil change is better for your car, but now we’ll further simplify this by discussing what exactly an oil change does to help your car. If you have ever wondered why oil changes are necessary, keep reading for answers.

What Is an Oil Change?

An oil change is exactly what it sounds like: it simply involves replacing the old motor oil in your car with new, fresh oil. This is done by draining the old, dirty oil, replacing the oil filter, and refilling the car with new oil.

What Does An Oil Change Do For My Car?

While it may sound like a simple, slightly unimportant task, regularly changing your oil is crucial for the well-being of your engine. Neglecting to replace your oil can lead to major issues, such as your engine overheating, running slowly, or even completely shutting down. Basically, if don’t properly maintain your engine’s oil, your engine will not last nearly as long as it could, and replacing or repairing an engine is never cheap. Engine issues, as well as other problems that result from improper maintenance of a vehicle’s oil, can cost an upwards of $4,000. Oil changes prevent these major issues from occurring by doing the following:

  • Keep the engine running smoothly. An engine is made up of numerous parts, which all work together at high rates of speed. The oil lubricates all of these various parts to help them run more smoothly, swiftly, and efficiently, minimizing friction in the process. The longer the oil goes unreplaced, the more it turns into a thicker, sludge-like substance which clogs your engine, rather than promote smooth functioning.
  • Cool down the engine. The engine can get extremely hot from the intense amount of friction that the moving parts create. Fresh, new oil serves as lubrication to prevent excessive amounts of friction, which subsequently keeps the engine cooler. The oil also helps to pull heat away from the combustion chamber, as well as prevents the engine from essentially blowing up.
  • Increase gas mileage. With gas prices dwindling upwards, you most likely want to optimize your gas mileage as much as possible. However, if there is a lack of clean oil in your engine, this leads to an increased amount of fuel consumption, as your engine must work harder due to lack of proper lubrication. Recent studies from the U.S. Department of Energy also show that regular oil changes can improve your gas mileage by 1 - 2%.
  • Encourage car longevity. Car technicians refer to the engine’s oil as the car’s lifeblood for a reason. If you take proper care of the engine’s oil, you promote the vehicle’s longevity, since the engine’s internal components will not have to work nearly as hard, as they are properly lubricated. After all, the healthier the engine, the longer the life span.

This animated video does a really good job of demonstrating how all of this occurs:

How Often Should I Get An Oil Change?

Regardless of what oil you use, it will eventually degrade. Due to high operating temperatures, the oil inevitably starts collecting dirt particles from the engine and undergoing thermal breakdown. When the oil has undergone so much thermal breakdown that it begins turning into sludge, this is when you should get an oil change.

Most people, however, are usually unaware of when their oil begins turning to sludge, so, luckily, there are a few different ways to tell when your oil needs to be changed:

  •  Car Owner’s Manual. Your car owner’s manual will tell you exactly how often your oil needs to be changed and what oil should be used. This stops you from having to estimate or assume when your next oil change should be.
  • The General Rule. The old rule of thumb generally suggests that an oil change should occur either every 3 months or after traveling between 3,000 to 5,000 miles. However, modern advances in engines and oil have begun to change this. So, although it’s a good, well-known recommendation to follow, you might be able to go a longer period of time than what is suggested. Check your owner’s manual to see what is best for your car.
  • Oil Change Stickers. One of the easiest ways to determine when you need an oil change is simply by following the oil change sticker typically on the left corner of your windshield. Your car technician should be able to examine your car, determine when exactly your oil should be replaced, and indicate this with a sticker. When your miles match the amount on the sticker or come close to it, it’s time for your next oil change.


Let Us Keep Your Car’s Engine Healthy


Our Reliable Import Service in Raleigh, NC will gladly maintain your engine's oil for you. Give us a call at (919) 821-1077 or fill out our online form to schedule an appointment today.


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