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How to tell difference between conventional and synthetic oil?

How to tell difference between conventional and synthetic oil?

Several car owners utilize high-grade oil to lubricate the vehicle motor and improve its functions and durability. According to consumer remakes, around 80% of individuals prefer synthetic lubricant over conventional for the latest vehicles.

How to tell difference between conventional and synthetic oil? Conventional and synthetic oil have differences due to non-identical composition, variable sources, distinct replacement gaps, and variable engine safety. Both have different mileage and non-identical types and costs.

Due to their appearance, both lubricants seem alike. They have different thicknesses and flow characteristics. 

Properties Synthetic oil Conventional oil
Composition Petroleum Crude oil/Natural source
Engine safety More Less
Replacement gap Long intervals Short intervals
Mileage 8500 to 17000 miles 4000 to 7000 miles
Oxidation and breakdown Less More
Examples 5W30 5W20
Price $60 to $150 $40 to $90

Composition and properties

Conventional oil is a cost-effective lubricant, with a derivation from crude oil, and provides performance for old cars. They are less durable due to their composition. 

Due to their less efficient properties, you cannot use them for a long duration. Also, their maintenance is challenging due to their less efficient properties. 

The old vehicles have a simple layout and less complicated machinery. For them, this fluid is beneficial because it can provide enough lubrication. 

Moreover, it has a slow flow and can move at a low speed. The old vehicles use it due to compatibility and enough durability. 

However, it can degrade quickly due to less effective composition. Also, it can undergo more chemical decomposition and cannot stabilize at various heat levels. 

Due to its thickness, its flow is slow, which cannot lubricate the machinery effectively. Due to the natural source, it cannot last for a few months due to the vehicle’s age. 

However, synthetic lubricants are beneficial for new models and the latest automobiles. This is because they have different natural compounds and artificial components. 

Also, they have specific chemicals which provide better performance. So you can fill them inside the latest automobiles to improve their stability and performance. 

Due to composition, you can categorize them into semi-synthetic and full synthetic lubricants. In addition, due to internal waxes, castor, paraffin, and other chemicals, they can perform effectively.

For optimized vehicle protection, they are beneficial. They can protect the machinery and run them at the highest performance. 

Variable engine safety

Due to its high performance, synthetic oil provides more engine safety. Moreover, it protects the motor from rusting because it can repel water and moisture.

In such circumstances, the engine remains safe from unnecessary wear and cracks. Also, it is resistant to contamination and secures the motor from damage.

With the automobile’s shelf life, they can protect the motor and keep it intact. However, conventional lubricants cannot secure the stability and performance of the engine.

It can form sludge due to dirt particles and reduces engine efficiency. In addition, due to its flow, the engine operation reduces from the threshold.

It can make deposits which reduces the internal cleaning of the automobile engine. However, it cannot stabilize at cold temperatures due to manufacturing compounds.

At these temperatures, it can settle in the bottom of the reservoir, which reduces its flow and lubrication ability. As a result, it cannot approach different motor parts, which reduces its security. 

Oil replacement gap

Synthetic oil has longer replacement gaps than conventional oils due to their stability and functions. However, it depends on the type of lubricant, the manufacturing company, and its usage. 

In such circumstances, the vehicle condition determines the replacement gap. Moreover, driving conditions and handling properties indicate the time requirements for their replacement.

In these conditions, you can check the automobile-related manual and follow the recommended guidance. Within the warranty, you can estimate the lubricant replacement gap according to the specifications.

Conventional lubricant takes fewer gaps for replacement because it has more weather and driving impact. You can lose it more quickly than the recommended limits with high-speed conditions.

Mileage and temperature stability

Synthetic oil has more stability at higher heat conditions than conventional lubricants. Generally, synthetic fluid can work best under pressurized conditions. 

Due to its refined properties, it cannot produce contamination. Moreover, it can provide a mileage of about 8500 to 17000 miles. It can alter according to the condition of the vehicle and its model. 

According to the lubricant quality, the mileage varies. For more clarity, you can consult an expert. 

However, the conventional lubricant is less durable and can cover a mileage of 4000 to 7000 miles. Therefore, you cannot use it for a long time without replacement because it cannot provide more miles.

Due to its low performance, the other parts crack, the filter break, and need maintenance.

Oxidation and breakdown

The synthetic lubricant does not require settlement time and work at cold temperature. Also, it approaches all the components for maximum lubrication. 

It stabilizes and does not break down due to complex composition elements. In addition, it does not evaporate due to heat.

With a stable molecular composition, it does not break down in various conditions. But, conventional oil does not stabilize and break due to its less effective composition.

The dimensions of molecules are different, which makes them less effective. In addition, due to minimum stability, it undergoes more oxidation than the counter lubricant. 


5W-30 is synthetic oil that increases engine protection and stability. Also, it can resist wear and cracks. It offers lubrication to moving shafts and engine pistons. 

It can clean the internal machinery due to cleaning characteristics. Moreover, 5W-20 is conventional oil that derives from natural crude fluids.

It comprises various additional elements for maximum engine working. With better stability, it can work under pressure and heat.

You can select it in the counter category, which has a fully synthetic base with various hydrocarbons, additives, and other compounds. Finally, 5W-30 is available as conventional oil, which has a crude grade for engine security from contamination and damage.

5W-40 is a specific lubricant with complete synthetic characteristics. It can support the motor effectively due to stability features. 

The first alphabets of examples show weight according to the attached number. The secondary numbers show the weight of thickness of the lubricant when the motor approaches the working temperature. 

Price differences

Synthetic oils are more expensive than conventional options due to minerals and high-quality making compounds. However, due to their durability, they have slightly higher costs than counter options.

It has an average price of about $60 to $150. To change it, you can spend nearly $80 to $160. The replacement price is higher because it requires minimum swaps due to longevity. 

The conventional lubricant is slightly less costly due to its performance and lifespan. In such circumstances, it has an estimated price of $40 to $90. 

Both have price differences according to quality, work, and durability. 

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