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What Is The Difference Between Transmission Fluid And Engine Oil?

Engine oil and transmission fluid basically differ from each other. Engine oil is a lubricant, while transmission fluid is a hydraulic fluid. Although they both may appear similar, they serve very different purposes. Engine oil helps enhance the engine’s performance and fuel efficiency. Transmission fluid supplies power to the hydraulic parts and vehicle’s transmission.

Engine oils are generally used for engine lubrication and cannot be used as a hydraulic fluid. So both these fluids have different roles to play. There are some notable differences between the two. Let’s understand further in great detail!

What Is Transmission Fluid?

Transmission fluid is used to lubricate the key components of a car’s transmission. It helps derive optimum efficiency and performance. Its purpose is to ensure seamless and smooth functioning of the entire transmission system.

What Is Engine Oil?

Engine oil or Motor oil is used for the lubrication of critical components of the internal combustion engines. It consists of base oils and lubricants integrated with various additives such as antiwear additives, dispersants, and multi-grade oils. It also improves the viscosity index to ensure the smooth functioning of the engine and its key parts.

Engine Oil

Is Transmission Fluid The Same As Engine Oil?

In simple terms, transmission fluid and engine oil are not basically the same. While they may look like similar liquids, they generally have different properties and uses. Transmission fluid is a type of hydraulic fluid that mainly supplies power from the engine to the transmission. There are different types of hydraulic oil lubricants, such as CVT fluid, brake fluid, power steering fluid, etc. Engine oil on the other hand is designed to efficiently deal with the combustion of the engine, whereas Transmission fluid plays hydraulic properties and does not see contaminants from fuel burning. These fluids work as a closed system so that it lasts for a long period of time.

Transmission Fluid Vs Engine Oil: Appearance

Appearance Of Engine Oil

  • Engine oils are generally translucent in color with a slight amber shade.
  • Engine oil has a lower viscosity than transmission oil, as it flows better between the components of the engine.
  • With time, engine oil gets darker. Old and Expired oil appears to be muddy.

Appearance Of Transmission Fluid

  • It appears to be green to sometimes dark red. Automatic transmission fluid or ATF tends to be red.
  • Manual transmission fluid is normally dark green.
  • CVT fluid is green and translucent.
Transmission Fluid

Transmission Fluid Vs Engine Oil: Applications And Functions

Engine Oil Applications And Functions

  • It provides protection against wear and friction.
  • Helps in maintaining the engine’s temperature as a coolant and helps with heat transfer
  • Engine oil keeps the engine free of sludge
  • It protects the engine from contaminants and impurities.
  • Protects against damage from water and corrosion

Transmission Fluid Applications And Functions

  • Manual transmission fluid is used for manual gearbox equipment whereas: Automatic transmission fluid finds its main use in the vehicle’s transmission system for working with a torque converter.
  • Additives are often added such as friction modifiers and coolant improvers.
  • Transmission oil (both manual and automatic) supports the smooth functioning of hydraulic parts.

Transmission Fluid Vs Engine Oil: Lifespans

Engine Oil Mileage

Depending upon the type of engine oil, it has to be replaced every 3000 to 6000 miles. Overuse of engine oil may impact the performance and cause damage to the engine components.

Transmission Fluid Mileage

Unlike engine oil, transmission oil lasts longer and doesn’t require changing until 30,000 to 50,000 miles. ATF (automatic transmission fluid) lasts even longer, around 60,000 to 100, 000 miles.

Both these fluids may seem similar, but they have different roles to play. Engine oil and transmission oil serve two different purposes. Engine oil helps improve and regulate the engine’s fuel efficiency and overall performance whereas transmission fluid helps in transferring power to the hydraulic parts and supporting the vehicle’s transmission. Regular maintenance and servicing is recommended for both these oils to work efficiently depending upon the vehicle’s needs.

Shield Lubricants are one of the best manufacturers of engine oil and transmission fluid with decades of experience and expertise. If you’re looking for the best lubrication oils, greases, and coolants for automotive, industrial, or marine applications, contact our experts today. We have years of experience and competence in providing high-quality products and services to all of our global clientele.

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