You need to change your vehicle oil every 3,000 to 10,000 miles depending on what type you use. If there are several types, how do you know which one is best? You should get a good understanding of the difference between conventional vs. synthetic blend vs. full synthetic oil.
This guide will cover all of the good and bad aspects of each of vented oil types. We will additionally cover how to choose the best type of oil for your car, as well as answer some of your most burning questions.
What is Conventional Oil?
Conventional oil comes from crude oil after it has been processed for use in the car engine. Depending on the process, there may be some differences at the molecular level to the structure of the oil.
This type of motor oil has been around since 1866 when John Ellis began the Continuous Oil Refining Company. During his exploration of the possible healing components of crude oil, he found out it lubricated machinery, making it a great choice for running engines. Initially, engines using oil were steam engines.
There was a time when conventional oil was the only type used in car engines. Today it is primarily used on vehicles with high mileage because conventional oil flows slower than synthetic oil, and high mileage vehicles tend to have worn out engines that need more protection.
Pros
Although the consensus among most auto technicians is that synthetic is a better oil overall, there are other aspects in favor of conventional oil. Here are just a few.
- Less Expensive: Conventional oils cost significantly less than synthetic oils. For the most part, the oil change is overall quite a bit less.
- Easier access to: Almost every auto repair shop along with any auto parts stores has access to conventional oils.
- Older Engines: The majority of older, 2000 and before, models were designed to use conventional oils, helping provide the proper lubrication.
- Protection for high-mile engines: The slower oil flow will only help a high-mile engine last longer.
Cons
The number of cons outweighs the advantages of conventional oils, making them more undesirable than desirable. Below are a few to consider.
- Less engine protection: In the modern engine, oil lines are narrow and thin. Conventional oils may not flow properly and provide lubrication.
- Less temperature protection: Conventional oils can work negatively in extremes of cold and heat. Cold makes conventional oil thicker, and heat can degenerate and evaporate it.
- Greater consumption: Conventional oils can virtually liquify and degenerate more quickly than many synthetic oils.
- Worse fuel economy: The more strain the engine has to endure or the harder the engine has to work, the more fuel will be used.
- Higher emissions: The more fuel that is burned, the more emissions are created.
- Short service life: You very well may have to change your conventional oil every 3,000 miles.
What is Synthetic Blend Oil?
Synthetic blends and semi-synthetic oils are essentially identical. Both consist of a motor oil that uses a mixture of synthetic and conventional formulas. However, there are no regulations that determine how much synthetic base oil there is, leading to a wide range of types and options.
In general, the synthetic blend would cost more and last longer than this conventional version. Similarly, it may not be as good as full synthetic, but is expected to cost less.
Pros
There are several advantages to using synthetic blends instead of convention oil. Here are a few:
- Less expensive than synthetic: You get almost all of the same benefits and characteristics of synthetic oil but at a slightly lower cost.
- Better fuel economy: Since the engine lubricates and does not have to work as hard, you should improve fuel economy.
- Lower emissions: Better fuel economy equals more efficient engine use, equals lower emissions.
- Specific detergents/additives: Companies incorporate certain types of additives and detergents to improve the engine’s health.
- Longer service life: You do not have to change the oil as frequently as convention oil.
Cons
There are some issues with synthetic blends that are important to know. Here the main complaints.
- More expensive than conventional: Synthetic blends typically will cost you more than a conventional oil change.
- It’s different: Because there are no regulations, there could be something that is greater than conventional, but the formula is not very different to conventional.
- Less availability: Not all places use synthetic blends. Many believe that this will go away as an option touting a better motor oil of full synthetic over the next few years.
What is Full Synthetic Oil?
Synthetic oil is formed from crude oil using artificial chemicals and additives to create a mirror image of petroleum. A group of German scientists first produced synthetic oil during the 1930s and 40s for use in the war. Synthetic automotive motor oils were not popular until the 1970s.
Since synthetic oils are manmade, they can have a variety of additives and detergents. Thus, every manufacturer produces a unique formulation that differs from the other manufacturers. Some are better at reducing sludge, while some may have anti-corrosion additives.
Pros
As more people choose synthetic motor oils, you probably want to know what that means for you. Here are some main points.
- Designed for today’s vehicles: Automobile manufactures design their new vehicles to optimize use of synthetic oil. The use of synthetic motor oil is recommended for variable valve timing, direct injection, superchargers and turbochargers.
- More chemical stability: The unique formulation allows the engine to perform better and in any temperature.
- Lasts longer: Oil changes may only be needed every 7,500 to 10,000; many drivers report less oil degradation with synthetic oils.
- Less likely to pollute the environment: Because less oil is lost through exhaust, fewer emissions create less pollution.
- Less engine deposits: Synthetic oil doesn’t leave the same deposits in the engine as other oil. A cleaner engine is a better performing engine.
Cons
Synthetic motor oils aren’t perfect. Here are some downsides to keep in mind.
- Higher price tag: You’re going to pay more for synthetic oil because there are costs involved in synthesizing it, and the company had to add detergents.
- Harmful to older engines: You shouldn’t run synthetic oils in older motors, and especially not in rotary engines. Synthetic oils damage the seals in these older motors which will be more costly in the long run.
How To Choose Oil Type For Your Vehicle?
What oil does my car take? It’s essential to know this before the next oil change. Make sure to at the very least know what is in the owner’s manual but also think of a few things.
Vehicle age
If you have a newer vehicle and low mileage you are likely going to want synthetic oil. It is designed for a newer engine especially if it has a turbo or supercharger.
If you have an older vehicle or one with high mileage you may want to use a conventional instead. It can help with more lubrication to help the life of your motor, at the very least you would want synthetic designed for high mileage.
Driving style
Your driving style greatly impacts what the motor needs. If you drive mostly city driving, you put your engine through a lot of wear. The stop and go driving wears on the engine over time. The engine may not have a chance to reach full temperature; it would probably be best to use synthetic oil.
Part of driving in urban settings is you will have to change the oil more frequently. If you do not get to the highway much you might consider changing the interval to be shorter to get more protection.
Cost
There are times you may not have a lot of cash to spend on car maintenance. This is definitely a challenge we understand, but as professional mechanics, we see car engines that fail prematurely from lack of vehicle maintenance.
In other words, NEVER skimp on an oil change. You can save some money on a conventional over synthetic oil, but you would be surprised to find out, it isn’t as much as you think based on how long it lasts until the next change.
Let’s say you are going to spend $45 for a conventional oil change. Well, it will last you approximately 3,000 miles until the next oil change. You will have paid 1.5 cents per mile.
Then again, you could spend $75 for a synthetic oil change, but it will last approximately 10,000 miles until the next oil change. Now you have paid less than a penny a mile. You have saved money in the long run.
So do the math before you assume that a conventional oil change has saved you money.
Changing Intervals
The frequency of changing the oil can impact which you choose as well. If you are okay changing the oil more frequently, conventional oil is an option. Generally, it lasts for 3,000 miles before it begins to break down.
Or, synthetic or a synthetic blend will get you more miles. Some synthetic oil is rated for 15,000 miles, but we do not recommend going that long.
Is synthetic blend oil better than full synthetic oil?
No, full synthetic has the best performance of the two but synthetic blend will have some of those same properties and additives without the high cost. It is reasonably priced, a little bit to more than conventional but slightly lower than full synthetic.
Is it OK to use full synthetic oil instead of synthetic blend?
A synthetic blend will have some of the same properties as a full synthetic but unless your owner’s manual states different oil, you should be fine with full synthetic. If you have an older model or high mileage, you may want to use something else.
Does synthetic blend oil last longer than conventional oil?
Yes, the synthetic blend will have some of the same properties as full synthetic and will last slightly longer than conventional oil, but probably not nearly as long as full synthetic will. Check on the package and see how long it is expected but always default to your automaker’s recommended maintenance schedule.
What are the drawbacks of synthetic blend oil?
Synthetic blend oils are not regulated, making it impossible to determine how much synthetic oil is actually included in each formulation, and brands will operate differently based on additives. Additionally, synthetic blends cost more than conventional oil.
When is it not beneficial to use full synthetic oil?
While synthetic oil can be used in most newer car engines (with many benefits to putting synthetic in a newer car) is not a good oil to use if your car is older, especially if you have a rotary engine.
These motors must use conventional oil to stay in good condition, and either way, if you have a high-mileage engine, that’s starting to have problems, you also want to avoid using synthetic oil as a high-mileage engine will need more lubrication.
Conventional oil is refined crude oil with no synthetic forms of oil added to it, which is the cheapest option but wears out the fastest. Synthetic motor oil is a man-made combination to keep the engine clean and perform to protect the engine from wear, it challenges the convention but is more costly and lasts longer. Synthetic blend is a mixture of the two.
Choosing between a conventional oil and synthetic or synthetic blend, is not difficult once you know what each form offers. Find what is recommended by the car manufacturer and keep up with maintenance schedule. That is the best way to ensure you get the best outcome from using your oil of choice.