Can I Use Motor Oil For Transmission Fluid [Explained]

Can I use motor oil for transmission fluid? You generally ask this question when you get run out of transmission fluid. We never recommend you to put motor oil into transmission in normal condition. But, you can use a tiny amount of motor oil for transmission, considering some risks. 

In this article, we will break down:

  • Why can’t you use motor oil for transmission?
  • Is transmission and engine oil the same?
  • Can you put oil in the transmission fluid?
  • What will happen if you use motor oil for transmission fluid?

So, stay in tune with us till the end.

Can I Use Motor Oil For Transmission Fluid?

No, you can’t use motor oil for transmission fluid. Motor oil and transmission fluid are two different products or oils to perform different jobs. The motor oil is thicker than the transmission fluid.

Consequently, it will clog up passages and likely cause more problems than fixing issues. Transmission fluid uses special detergents and additives as its built-in material for your vehicle’s transmission system. Using other oils like engine oil will damage rather than lubricate the transmission. 

The motor oil or engine oil is especially concentrated to lubricate the moving parts of your engine. It lubricates each moving engine part and reduces friction between them. Therefore, it prevents sludge from forming and protects your car engine. On the other hand, the transmission fluid enhances the operation of your transmission systems by lubricating them. If you put engine oil into the transmission system, it can’t do any more good than bad. 

In short, we don’t recommend you use motor oil for transmission fluid. If you want to keep your clutches, gears, and overall transmission systems lubricated, use the recommended oil only. 

Is Transmission Fluid The Same As Motor Oil? [The Differences]

Transmission fluid is not the same as motor oil. The viscosity rate, color, life span, consumption rate, and the detergents it uses are different from the motor oil. Besides, the purpose of the transmission fluid and motor oil is not the same. 

Below, we will break down the answer to this question: Is transmission and engine oil the same?. Indeed, we will depict the differences between the transmission fluid and the motor oil. 

Appearance or Color

The first visual difference between transmission fluid and motor oil is their appearance. Transmission fluid is green or dark red. However, the color of ATF (automatic transmission fluid) is red while the manual transmission fluid is dark green. 

On the other hand, motor oil is translucent in color with a yellow or golden hue. It starts getting darker as the engine oil ages. The viscosity of it will also break when it ages. 

Oil Change Interval or Lifespan

Both oils (motor and transmission oil) are affected by mileage and time. Generally, you can go or drive your car with transmission fluid up to 30,000-60,000 miles between oil changes. On the other hand, you should change the engine oil 3000-6000 miles. Indeed, transmission fluid lasts longer than engine oil. 

Purpose or Application

Both transmission fluid and engine oil are a lubricant. But the purpose or application of these two fluids is different. 

The transmission fluid is formulated to lubricate the transmission system of your car. You can find two different transmission fluids in the market: manual and automatic. 

Manual transmission fluid is used to lubricate the gearbox. And the automatic transmission will help to lubricate the torque converter. 

On the other hand, engine oil is especially concentrated to keep the moving parts of your engine lubricated. It provides superior engine protection against sludge and regular wear & tear. 

You can find three different engine oils in the market, including synthetic, semi-synthetic, and conventional. 

Can You Put Oil In Transmission Fluid?

No, you can’t put engine oil in transmission fluid and mix them. The viscosity of the transmission fluid and motor oil is different. Generally, engine oil is less viscous than the transmission fluid so that it can flow to the top of the engine with ease. On the other hand, the transmission fluid is thicker, and it is specially used to lubricate the clutches, gearbox, and transmission systems. 

Indeed, you can’t use engine oil as transmission fluid. If you put the motor oil in the transmission fluid and use it in the transmission system, it will damage it.  

What Will Happen If I Use Motor Oil For Transmission Fluid?

If you put motor oil into the transmission accidentally, it causes little to no damage in most cases. However, you will notice or experience significant bad effects if you use too much motor oil and let it remain there. You will observe the following signs if you use motor oil for transmission fluid:

  • You can feel the grinding or shaking movements when changing gears.
  • You can’t get quick responses from your car when shifting gears. Indeed, malfunctioning gear is the ultimate result due to the use of motor oil for transmission. 
  • You will experience gear slipping. 
  • The gearbox will produce knocking noises because of the wrong oil in the transmission. 
  • A burning smell will come out of the transmissions. 

However, you can easily avoid these problems. Just flush the motor oil from the transmission as soon as you can. Check out this tutorial if you don’t know how to flush transmission fluid. 


Can power steering fluid be used as transmission?

The steering fluid and the transmission fluid are the same. Both are hydraulic fluids, and it seems they can be used as an alternative to each other. Modern cars use delicate parts and engineering techniques. If you use steering fluid as transmission fluid, it will damage those delicate parts of your vehicle. So, we recommend you to not use the power steering fluid as a substitute for transmission. 

Can you substitute transmission fluid for brake fluid?

No, you can’t substitute transmission fluid for brake fluid. These two oils use different ingredients as their built-in material. It means they are not compatible. If you use transmission fluid as brake fluid it will damage the brake components. 

Can you use motor oil as a steering fluid?

We don’t recommend you use motor oil as a steering fluid as a high amount of engine oil will attack the O-rings or seals of the steering system and damage them. However, you may use a small amount of motor oil if you run out of steering fluid. 

How long can a car run without transmission fluid?

You can run or drive your car for up to 10 miles without transmission fluid as long as you run the car slowly. 

Is there a universal transmission fluid?

Yes, there is a universal transmission fluid, and it’s Ultra1Plus™ ATF Universal Full Synthetic Transmission Fluid. You can use it in almost every vehicle regardless of its makes and models. 


In a quick recap, you can’t use motor oil as an alternative to transmission fluid as both are two different types of oils. However, putting a short amount of engine oil into the transmission will not bring any significant damage if you flush the oil quickly. 

But you can experience several issues (we mentioned them above) if you use too much motor oil in the transmission. 

The best suggestion we can give is to check the transmission fluid level. When it gets low, change it with the recommended transmission fluid. Generally, you need to change the transmission fluid every 30000-60000 miles. 

About John M

John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.

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