Is Transfer Case Fluid The Same As Transmission Fluid? A Detailed Explanation

Like many vehicle owners, are you wondering, “is transfer case fluid the same as transmission fluid?” Well, both of these lubricants are completely different.

The transfer case and tranny oil both have a great impact on the car’s overall performance. Based on their respective purposes, these liquids’ working process is quite the opposite.

We have discussed these two fluid types, including their differences and other helpful stuff here. So whether you are a car owner, mechanic, or just curious, read on to learn everything about these crucial items.

Is Transfer Case Fluid the Same As Transmission Fluid?

In simple words, no, they are not the same.

The transfer case is situated between rear differentials and front differentials. It works by distributing transmission power to wheels. The process requires fluid which gives cooling and lubrication to its inner parts (gears). This results in flawless driving and smooth gear shifting without any wear.

In a few cars, the liquid work as wet clutch lubrication. Gear oils are often applied in the majority of vehicle transfer cases. On the contrary, the new generation cars need specialized ones. In certain cases, a number of cars can be filled up with the ATF (red color), but it solely depends on the manufactures recommendations.

Tranny fluid is a lubricant that helps improve the performance of a car’s transmission. It helps the bearings and gearbox metals run smoothly. Plus, the liquid provides gear shifting, hydraulic friction, and pressure. Also, it protects the clutch and gears. Furthermore, the oil keeps the part in a cool environment.

According to the Universal Technical Institute, without transmission fluid, the gears of the car would overheat and wear out quickly, which may end up in transmission life and a high repair cost.

Transfer Case Oil Vs Transmission Fluid

It is important to know the difference between these two lubricants to differ correctly. Transmission oil is used to move the gears and other parts within the transmission. It also works in hydraulic systems. In contrast, transfer case liquid is used for vehicle power and traction. Check out the main differences among these below:

Working Area/Operating area

One of the main comparison aspects between these 2 fluids is the operating area in the vehicle. As the name suggests, these liquids operate respectably in the transfer case and the transmission system.

Transfer case oils protect the gears from wear by keeping them lubricated. However, the transfer case might fail or stop functioning if the oil became old or tainted enough.

Tranny fluid helps in transferring power inside the transmission. Plus, it lubricates the moving components and guarantees smooth gear changing. If this fluid level drops too low, the transmission will fail.


Both transfer case and transmission fluid have different viscosity where one has higher and other has lower. The typical viscosity of transfer case oil is about 75W/90, whereas in tranny oil, it’s between 0W/5 to 5W/10.

High viscosity protects the gears from shock and guarantees that the inner parts are adequately lubricated. On the contrary, in tranny oil, the viscosity is maintained at a low level so that it can properly lubricate the transmission’s components. To transfer the engine’s power to the transmission, it is crucial that the fluid be somewhat free-flowing.

Built Material

These oils are made with different materials. The ingredients used to create these oils determine their colors.

Polyglycerols or hydrocarbons are used to make transfer case fluid. Depending on whether gear oil or specialized fluid is used, the color will range from green to yellow to blue to brown.

Automatic and manual transmissions are the two most common kinds of transmission systems. Therefore, the fluids are Automatic Transmission Oil and Manual Transmission Oil. The highly complex hydrocarbon or petroleum base ATFs are formulated with a wide variety of components. On the other hand, MTF is a fully synthetic fluid. New transmission oils are crimson in color. Once tainted, their color changes to black or brown.

Heat Resistance

Transfer case liquid can tolerate extreme heat. It mainly transfers the temp away without evaporating too quickly. On the other hand, transmission oil has a lower boiling point.

Replacement time

It is strongly suggested that these liquids be replaced after a specific amount of time. Timely replacement ensures that the parts operate properly.

The transfer case oil may grow into dirty condition after a long time of usage. The lubricant process will not work in the transfer case that contains dirty fluids. Thus, maintaining it on a regular basis is required.

The maintenance depends on the vehicle model; check the owner’s manual as it indicates the oil changing mileage. In most vehicles, it is between 20,000 miles to 30,000 miles. Furthermore, a vehicle’s transfer case should be checked often regardless of how often you drive on paved roads, but more so if you take it towing or off-roading.

The tranny oils last longer. However, the fluid may get tainted with metal debris due to the constant rubbing of gears against the shaft. The oil that has been contaminated by pollution is no longer effective in reducing friction, which has a negative impact on performance. In the worse case, this may even cause transmission failure. So, changing in a timely manner is highly necessary. For ATF, it’s about 30,000 miles to 100,000 miles, and for MTF, it is between 30,000 miles to 60,000 miles.

Does the transfer case and transmission share fluid?

No. As both of these oils are used in separate vehicle parts, there is no sharing involved. The reason behind this is their purpose and functionality.

The transfer case liquid work with the gear oil (85W90), and the transmission liquid uses various one.

Note: Never mix and apply these oils because they will damage the vehicle

Is transfer case fluid the same as gear oil?

No, they are different. The gear oil is mainly used in older vehicles, while the transfer case liquid is specifically made for newer models.

Frequently Asked Questions (FAQs)

Can you use transmission fluid for the transfer case?

You can definitely use the tranny oil. But, keep in mind to check the manuals or talk with your car mechanic before using. Because older car or new car model uses only gear oil or specialized made oil for this component. So, applying the liquid might not be ideal in these cases.

What’s the best fluid for a transfer case?

Experts recommend the 75W90 or the 85W90 gear oils are the perfect ones. However, automatic transmission oils are also popular with many car owners.

What is a transfer case fluid?

The liquid that is applied in the transfer case mainly lubricates its inner material of it. It makes sure to draw the gear heat away as possible and helps in greater performance and prolonging the part life.

What is a transmission fluid?

It is an oil composed to protect the car’s clutch and gears while providing smooth gear shifting. Without this liquid, gear will quickly damage or overheat. Thus, the transmission can fail while driving the vehicle.

How often should transfer case fluid be changed?

In general, after 30,000 miles of driving, the oil should be checked, and changing is a must if any bad symptoms are found. While replacing, be careful. Always check the fluids after the required period to keep your car in its best shape.


Both the transfer case liquid and tranny oil have their own characteristics and are used in different parts with different purposes. Knowing these fluids can help owners to face any issue related to these important components.

With the above information, it is now clear that the liquids are completely different. Hopefully, the article on is transfer case fluid the same as transmission fluid cleared your doubts.

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