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The Importance of Car Gear Oil in Vehicle Maintenance

The Importance of Car Gear Oil in Vehicle Maintenance

The transmission mechanisms in your vehicle involve extensive contact between metal components, resulting in heat generation and damage over time. Car Gear oil plays a crucial role in safeguarding these moving parts by minimizing friction and dissipating heat effectively. Regularly replacing your car’s gear oil is a vital maintenance task that prolongs the lifespan of your vehicle while preventing expensive repairs in the future.

What is Gear Oil used for?

Gear oil serves as a specialized lubricant specifically designed for various components in your vehicle, such as transmissions, manual gearboxes, differentials, transaxles, and transfer cases. Its primary function is to ensure the smooth operation of the transmission system. However, its significance extends beyond that, as it plays a crucial role in safeguarding vital internal elements of your car’s gear mechanisms against both wear and heat-related damage.

Inadequate lubrication can result in the scouring, corrosion, scuffing, and pitting of important drivetrain components. This deterioration can compromise your car’s performance, and eventually lead to costly repairs. Gear oil and motor oil are not the same thing, and they are not interchangeable. Gear oil is specially formulated for use on gears. Motor oil… You guessed it – it’s for motors.

How do I know which car gear oil to use?

It is crucial to consult your vehicle’s owner’s manual to determine the specific gear system specifications for your automobile. Gear systems can vary between different vehicles, and using the incorrect gear oil can have negative consequences, such as diminished performance or potential damage to internal components. To ensure optimal performance and protection, it is essential to strictly adhere to the gear oil recommended by the manufacturer of your vehicle. The owner’s manual will provide you with accurate and appropriate information regarding the type of gear oil that should be used.

Gear oils are evaluated and graded by the American Petroleum Institute (API) based on their overall performance. The two most commonly available grades in the market are GL-4 and GL-5. GL-4 gear oil is typically required for the majority of cars. However, heavy-duty vehicles or high-performance automobiles such as trucks and sports cars may necessitate the use of GL-5 gear oil.

It’s important to note that GL-4 and GL-5 are different specifications, with GL-5 offering enhanced performance characteristics compared to GL-4. When selecting gear oil for your vehicle, it is crucial to consult the manufacturer’s recommendations in your owner’s manual to determine the appropriate API grade (GL-4 or GL-5) for your specific vehicle model. Adhering to the correct gear oil specification will help ensure optimal performance and protection for your vehicle’s gear system.

What happens if you don’t change your car gear oil?

Neglecting to adhere to the manufacturer’s recommended schedule for changing your gear oil can pose a significant risk of severe damage to your vehicle’s transmission and other gear systems. This can lead to the need for costly repairs and parts replacements.

Over time, gear oil experiences degradation. Manual transmissions and other gear systems involve extensive metal-on-metal contact, causing friction that gradually wears down the moving parts. Additionally, tiny metal particles accumulate in the gear oil as a byproduct. These factors eventually diminish the lubricating properties of the gear oil. Consequently, if the gear oil is not periodically drained and replaced, it will accelerate the wear and tear on your transmission, thereby reducing its overall lifespan.

How often should gear oil be changed?

Before making any decisions, it is advisable to refer to your vehicle’s owner’s manual for the most accurate and specific recommendations. However, under normal driving conditions, general guidelines suggest changing the gear oil in an automatic transmission every 48,000 to 80,000 kilometers (30,000 to 50,000 miles). For a manual transmission, the interval is typically longer, ranging from 96,000 to 160,000 kilometers (60,000 to 100,000 miles).

In the case of vehicles subjected to severe conditions such as towing heavy loads or frequently driving through challenging terrains like mud, it may be necessary to change the gear oil more frequently. In such instances, it is generally recommended to have the gear oil changed as often as every 24,000 kilometers (15,000 miles).

Remember, these are general guidelines, and it is always best to consult your owner’s manual or seek advice from a qualified professional to determine the precise intervals suitable for your specific vehicle and driving habits.

What are the signs that the car gear oil should be changed?

It is important to be attentive to the behavior of your transmission to identify signs that indicate a need for a gear oil change. Here are some indicators to look out for:

Shifting Issues

If you experience slipping or thumping sensations when shifting gears, it may be a sign that your gear oil needs to be replaced.

Unusual Smells and Sounds

Strange burning odors, whining noises, or grinding sounds during gear shifts can indicate that the gear oil is deteriorated and requires a change.


Keep an eye out for any signs of leaks around the transmission area. Leaks can suggest that the gear oil has become contaminated or that there is a potential issue with the transmission.

Dark or Gritty Gear Oil

If you check the gear oil and find it to be dark or contaminated with debris, it is a clear indication that it is time for a gear oil change.

“Check Engine” Light

If the “check engine” light illuminates your dashboard, it is always recommended to promptly address the issue as it may be related to the transmission or another vital component in your vehicle.

Gear Oil brands

Some of the gear oil brands are as follows:


ATF gear oil, short for Automatic Transmission Fluid gear oil, is a specialized lubricant used in automatic transmissions. It serves multiple functions to ensure smooth transmission operation and protect its components. Composed of a blend of base oils and additives, ATF gear oil provides lubrication to minimize friction and prevent wear and damage. It also acts as a hydraulic fluid, enabling seamless shifting of gears and controlling various transmission components. The viscosity of ATF gear oil varies according to different grades, ensuring optimal flow characteristics at varying temperatures. It’s important to use the ATF type recommended by the vehicle manufacturer to maintain compatibility and performance.


PSO Gear Oil refers to the gear oil products manufactured by PSO (Pakistan State Oil), a leading oil marketing company based in Pakistan. PSO produces a range of lubricants, including gear oils, designed to provide optimal performance and protection for various types of gears and transmissions.


SGO Gear Oil typically refers to the gear oil products manufactured by Shell Global, a multinational energy company. Shell produces a range of lubricants, including gear oils, under the SGO (Shell Gear Oil) brand.
SGO Gear Oil is designed to provide excellent protection and performance for various types of gear and gearboxes. It is formulated using high-quality base oils and advanced additives to ensure optimal lubrication, reduce friction, minimize wear, and prevent corrosion. SGO Gear Oil is available in different viscosity grades to suit different gear systems and operating conditions.


Gear oil holds great significance in vehicle maintenance due to its crucial role in protecting and optimizing gear systems. By providing necessary lubrication, gear oil safeguards internal components from wear, friction, and heat damage, thereby prolonging their lifespan. It ensures smooth gear shifting and optimal performance, contributing to the overall efficiency of the vehicle. Regularly changing the gear oil prevents the accumulation of contaminants, preserving its lubricating properties and preventing costly repairs. Adhering to the manufacturer’s recommendations, using the appropriate gear oil grade, and promptly addressing any issues ensure the reliability, efficiency, and longevity of the vehicle’s gear systems. Thus, proper gear oil maintenance is essential for maintaining a well-functioning vehicle.