Synthetic vs. Conventional Oil || Which Is Better

Any car enthusiast, seasonal or professional driver needs to feed their vehicle’s engine food. 

As synthetic and conventional, both motor oils are used to run engines. So there arises a dilemma among them between these oils. 

Which oil to choose?

Which oil increases mileage efficiency, smooth performance, and engine lifespan? 

Which oil is budget-friendly? 

And many more questions. 

Synthetic oil is more refined, pure, and chemically stable than conventional oil. So this oil can offer you higher protection, smoother performance, and better longevity. 

Conventional oil is a crude, petroleum-based lubricant. Provide less wear and tear protection, and need a frequent oil change, but reasonably priced. 

However, in this post, I’ll show you all the detailed differences between Synthetic vs. Conventional Oil. So you can choose the right oil for your engine. 

What Is Engine Oil & What Is Its Purpose?


Before the main discussion, let me briefly describe engine oil and its purposes, as it’ll help you understand the further points. 

Typically, motor or engine oil is a liquid form of substance that is used as a lubricant. Vehicles’ engines are made from lots of metallic components. And during their operation, they come in contact with each other, especially the time of hauling or towing. Engine oil works as a lubricant to avoid metallic friction and improves smooth movement. 

Synthetic vs Conventional Oil Comparison Table

Features Synthetic Oil Conventional Oil
Used for Modern and New enginesOlder and small engine
Viscosity grade0W-20, 5W-30, 5W-40, 10W-30, 10W-40, 15W-40 and 20W-50.5W-20, 5W-30, 10W-30, 10W-40, 20W-50
Heat ResistanceBetween 250-500°F or 121-260°CBetween 200-225°F 93-107°C
Flash point440°F or 226°C400°F or 204°C
Pour point-85°F or -65 °C-25°F or -32°C
Film strength Higher Lower
Pressure handling capacity Excellent Average 
Cleaning capabilitySuperior Average 
Oil changing interval (Milage)7500-10000 miles or 6 months 3000-5000 miles or 3-6 months 
Compatible vehicles ATVs, SUVs, UTVs, Motorcycles, Lawnmowers, Boats, etc. Trucks, Pickups, Sedans, Vans, etc. 
PriceSlightly priceyBudget-friendly

Overview of Synthetic Motor oil


Synthetic motor oil is engineered in the laboratory instead of pumping out from the ground. Its molecules are specific and contain properties like anti-wear and anti-sludge additives. 

It flows faster between the engines’ hard-reach parts even in high temp weather. So, it’ll offer you excellent protection against wear and tear.

This oil also lasts longer due to less breakdown or vaporization. That means you can enjoy higher miles driving with the same oil. It’ll indirectly increase fuel economy and decrease oil change intervals. 

Moreover, the compatibility of synthetic motor oil is higher than conventional oil. You can use this oil in your gasoline, diesel turbocharged, High-performance, and Hybrid engines. So you won’t need to consider your engine types to choose synthetic oil. 


  • Offer sufficient protection against wear and tear
  • High temperatures and oxidation resistance for hot weather 
  • Improved engine’s smooth performance & efficiency
  • Longer oil change intervals with less fuel cost


  • At least 10% high price than conventional oil

Overview of Conventional Motor oil


Conventional or mineral oil is directly extracted from or pumped out crude oil. Though it isn’t formulated in the lab, certain additives are included to reduce its impurities. But, the amount of additives isn’t as much as synthetic oil. 

However, that doesn’t mean this oil is entirely worthless. Instead, it can offer essential protection from rust and corrosion. Prevention from sludge and deposits. And performance efficiency in low temp weather conditions. 

Since this oil breaks down faster than synthetic oil, it needs frequent changes. Otherwise, the impurities will reduce its effectiveness in lubing the engine’s parts. 

In addition, some vehicle manufacturers recommend conventional oil for their vehicles. Even due to the affordable price of the oil, many users love to use this oil on their older or classic cars, lawnmowers or motorcycles, lower-performance engines, etc. 


  • Efficient in winter season to flow faster 
  • Right choice for stop-and-go drives  
  • Compatible with older engines 
  • Less fuel cost for an affordable price


  • Not effective in modern engines and longer drives 

Synthetic vs. Conventional Oil Detail Comparison

So, you get a basic understanding of oils from the table and general overviews. Now, it’s time to describe the oils feature by feature to get the winner.  

1. Types of oil

Different types of vehicles are available and they are used for different purposes. Depending on their objectives, they also come in various types of engines. 

So, it’s obvious the same oil won’t be worthwhile for all of them. Considering these factors, both synthetic and conventional oil comes in different types. Such as 

Synthetic oil

The main three types of synthetic motor oils are regular, high mileage, and extended performance. 

You choose the general synthetic oil for regular use in your UTVs and ATVs. The high mileage oil is good to use in higher mileage engines more than 75000 miles. They can be Toyota Camry, Honda Civic, Ford F-150, Chevrolet Silverado, or Dodge Ram 1500. 

However, if you have a car from BMW 5 Series, Mercedes-Benz E-Class, Audi A6, Porsche 911, or Chevrolet Corvette, you must choose extended-performance synthetic oil. 

Conventional oil 

Mineral-based, Synthetic blend and High mileage are the three types of conventional oils. Each of the oils is made with unique additives and properties. 

Mineral-based oil is suitable for older engines. But, the Synthetic blend is ideal for older vehicles with less demanding engines. 

On the other hand, for older vehicles with 75,000+ miles engine, high mileage conventional oil will be the right choice for you. 

Winner: Synthetic Oil

2. Viscosity Grade 

Viscosity grading is the measurement of the liquidity rate of the oil. The viscosity grade is formed with “2 digits and w in the middle”. Here the first digit refers to the lowest temperature resistance level when the last number is higher. And the w means winter. 

Synthetic Oil

Every regional area of the world doesn’t have the same weather conditions. Even all year, the weather also won’t remain the same. So, the motor oil brands bring multiple viscose synthetic oils from 0W-20 to 20W-50. As a result, you can choose the oil keeping in mind your local weather conditions. 

Conventional Oil 

Since old engines are already fragile, they need extra care to rejuvenate their horsepower and performance. You’ll find 5 different viscose conventional oils in the market. Such as 5W-20, 5W-30, 10W-30, 10W-40, 20W-50. You can pick the one that recommends your OEM and fits your engine.  

Note: The thumb rule to select the synthetic oil’s viscosity is that the lower the temp, the lower the consistency. And vice versa. 

Winner: Synthetic Oil

3. Protection & Performance

No matter which oil you put into your vehicle’s reservoir. That won’t be worth it unless the oil protects your engine from heat, wear, and deposits. So, you can’t enjoy driving and may need expensive repairs. 

In this case, it’s essential to know the protection and performance ability of both oils to get the winner. 

Synthetic Oil

This oil has to pass various tests in the laboratory. That means, in quality, synthetic oil is beyond any doubt. 

Synthetic oil will lube pistons, bearings, and other metallic components effectively. So when you run the engine, they won’t come in contact and torque smoothly. This is how this oil ensures better protection for the engine against rust and corrosion. 

When the engine runs its best, you’ll get top-notch performance even on uneven surfaces and bumpy roads. 

Conventional Oil

Conventional oil is less effective in higher protection and performance as crude oil is poorly refined than synthetic oil. 

However, driving on city roads won’t create too much pressure and stress on the engine. So, in this situation, conventional oil can offer adequate protection to increase engine life expectancy. But it’s true, that won’t be as equal as synthetic oil. 

On flat terrain, you’ll also get smooth driving with this oil. But, on bumpy and dusty roads, that can be challenging. 

Winner: Synthetic Oil

4. Heat Resistance Level

Other differential points between the oils are their heat-resistant level. Whether modern or older, the engines have to withstand high heat. 

Because when the engines run, they produce heat from inside. And the natural heat also affects the engine from outside. This is why the higher the heat the oil can withstand, the better.  

Synthetic Oil

This oil can handle too much pressure and stress due to containing multiple additives, agents, and other properties. Typically, it can remain clean under harsh weather when you sweat. 

Depending on brand and viscosity grade, synthetic oil can withstand 250 to 500°F or 121-260°C. You can use the oil on the hottest days with no challenges of losing weight. 

Conventional Oil

Conventional oil will remain fluid to flow under 200-225°F 93-107°C temperature. It can offer you better protection and performance within this temperature range. So you shouldn’t use this oil for a high-heat area or season. 

Winner: Synthetic Oil

5. Shear Stability/Oil changing Interval 

The more the oil remains clean after driving, the better the shear stability of the oil. Staying the oil clean for longer is essential to improve fuel economy. It even helps to prolong engine longevity with less impact. 

Synthetic and conventional oil both come with different shear stability. Such as

Synthetic oil 

Though oil shear stability or changing Interval depends on several factors. Like the age of your engine, driving skills, and weather conditions. 

However, regular synthetic oil will remain clean up to 7,500-10,000 miles. You have to change the oil within this mileage range. However, in the time frame it will be 6 months.

For High-mileage synthetic oil, it’ll be good to use up to 15,000 miles or within 1 year. And for Extended performance synthetic oil, it’ll be 20,000 miles or within 1 year.

Conventional Oil 

Like any features, conventional oil also offers less mileage efficiency between oil changes. 

If you use regular conventional oil, you can go 3,000-5,000 miles or between 3-6 months. While 7,500 miles or 6 months for high mileage traditional oil. 

Winner: Synthetic Oil

6. Price

The last distinction between synthetic and conventional oil is its price. It’s also essential for you to save your wallet without compromising engine optimization. 

Synthetic Oil

This oil is more expensive than conventional for better quality, viscosity, and versatility. But, comparing your peace of mind driving, high mileage efficiency, and longer engine life with less repairing cost, the price is okay. 

Conventional Oil

This is the one winning points for conventional oil. It is affordable and available in local stores. It can be a good choice if you need oil for regular driving. 

Winner: Conventional Oil

Synthetic vs. Conventional Oil (What To Choose)

You can choose both oils considering your vehicle’s OEM recommendation, engine condition, driving skills, and weather conditions. For example 

  • If your vehicle manufacturer recommends synthetic oil, you should use synthetic oil. When your vehicle manufacturer recommends conventional oil, you should use conventional oil.
  • If your vehicle’s engine is new, go with synthetic oil. If your vehicle’s engine is old, go with conventional oil.
  • If you live in a summer-based region, choose synthetic oil. If you live in a winter-based area, choose conventional crude.
  • If you need regular driving and save a penny, choose conventional oil. If you need long drives and higher protection, choose synthetic oil. 

These are some of the situations when choosing which oil. Use your sense and logic to get the best answer.

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