Understanding the Different Types of Engine Oil

Understanding the Different Types of Engine Oil
| By: Christian Brothers Automotive

If you’ve ever stepped into a local auto parts store and browsed the motor oil aisle, you’ve probably been overwhelmed by the number of choices there are. There are countless brands, quantities, weights, additives, and types of oil to choose from – how in the world could anyone know what kind of engine oil is right for their car?

Finding the right type of engine oil for your car is actually not as difficult as you may think! If you simply consult your vehicle’s owner’s manual, you’ll find out exactly what your car needs. Your car’s manual should indicate the required:

  • weight of oil
  • frequency of oil changes
  • volume of oil

These are all important figures to know, but your manual may not include what type of oil to get. As you may have guessed already, not all engine oils were created equal. The type of oil you put into your car significantly impacts your engine’s efficiency and health, so it’s important to do some proper research before throwing any oil you can find into your car.

Editor’s Note: This blog has been updated as of 2023 to reflect current industry standards and technical knowledge.

What Are the Different Types of Engine Oil?

Here are the four main classes of engine oils:

  • Conventional motor oil
  • Synthetic motor oil
  • Synthetic blend motor oil
  • High-mileage motor oil

In this blog, our auto repair experts will dive into each of these motor oil classes, the effects they can have on your engine’s performance, and which one is right for your vehicle. We’ll also share recommendations on how often to change your oil.

Conventional Oil

Conventional oil is your standard motor oil. It’s manufactured from crude oil that’s pulled from the ground and then refined in a factory – just as it’s been for hundreds of years. Different additives and processes are done to improve its viscosity (thickness) and engine-protecting properties, and it’s then bottled and sold for use in your engine. It’s as simple as that.

As with anything, each oil type has its pros and cons. When it comes to conventional motor oil the biggest upsides are:

  • It’s affordable
  • It keeps your car running smoothly

Conventional oil is an extremely budget-friendly option, is ideal for regular driving habits and simple design cars, and is effective at its job. To be honest, there aren’t any bad motor oils on the market nowadays. As long as you get the right weight and quantity (which is included in your car’s manual), you can expect reasonable performance.

On the other hand, the downsides of conventional engine oil tend to be more than the others. Due to the naturally occurring materials it’s sourced from, the oil tends to be less refined, requiring oil changes pretty often. Around 5,000 miles, to be exact!

And, when it comes down to it, conventional engine oil offers a lower degree of protection than the others, even with additives. If you can swing it, upgrading to a better engine oil class is often worth the money.

Full-Synthetic Oil

Synthetic motor oil is manufactured entirely in a factory or lab, which ensures that the quality of the oil and performance remains consistent. This is because it’s far easier to control manufacturing processes when all your materials are held to many more stringent standards instead of relying on naturally occurring sources.

Synthetic oils are more refined and are overall better for engines. They provide several advantages over other motor oil classes:

  • Fewer oil changes are required due to synthetic oils lasting upwards of 10,000 miles
  • Flows better at lower temperatures
  • Better protection against deposits in your engine

With so much to benefit from, why isn’t everyone using it? Well, for one, not all engines need or accept it. Additionally, full-synthetic motor oil comes with a heavier price tag, making it far more expensive than conventional motor oil. You can expect to pay an extra $20 to $40 for your oil change if you use synthetic oil, depending on how much oil your car requires.

Synthetic Blend Oil

Synthetic blend oils are a kind of hybrid oil manufactured from both synthetic and natural materials. Essentially, it is a blend of both conventional and synthetic oils to try to capture some of the benefits of both while reducing their drawbacks.

The results are pretty much exactly what you’d expect:

  • Synthetic blend motor oil provides better protection and performance than conventional oil but is not quite as good as full-synthetic oil
  • Synthetic blends last a little bit longer than conventional oils but not as long as full-synthetic
  • Synthetic blends cost a little bit more than conventional oil but not as much as a full-synthetic

Overall, synthetic blend oil is a great middle-ground for those looking to give their car a little more help but keep costs down, because it tends to be just a bit more expensive than your average premium brand conventional oil but less expensive than full-synthetic oils. With synthetic blend oil, you can expect an oil change around every 7,500 miles!

High-Mileage Oil

High-mileage oil is a somewhat unique branch of oil that’s entirely on its own. These products include a blend of unique additives designed to help protect engine seals, which in turn helps prevent oil evaporation and improves overall performance.

For cars that are getting a little long on the odometer, this extra protection is key as oil burn-off (or oil burn out) becomes a little bit more common of a problem, contributing to more engine wear and a decreased lifespan. In summary, high-mileage motor oils can help:

  • Prevent engine oil leaks
  • Curb motor oil burn-off
  • Reduce exhaust emissions

If you drive a car over 75,000 miles, it’s strongly advised that you use high-mileage oil. You won’t regret it; it can help you get more out of your engine and prevent a number of problems!

Need an Oil Change? Christian Brothers Automotive is Here to Help

While you can certainly drain and replace your car’s oil in the comfort of your own driveway as long as you know how to do it correctly, it’s recommended to bring your car into a local auto shop instead. This not only offers you peace of mind that it’ll be done right, but also you’ll be able to get some expert advice on what type of oil is best for your vehicle as well as how often your oil should be changed.

For over 30 years the auto repair experts at Christian Brothers Automotive have offered quality care and maintenance services for your vehicle, including full-service oil changes. Whether your car is brand new or has hundreds of thousands of miles on the odometer, you can trust our ASE-Certified technicians to ensure it’s running at its absolute best and is well cared for.

Looking for more information for your next oil change? Check out more of our blogs or find your closest Christian Brothers Automotive location!

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