Can I Use Motor Oil For Transmission Fluid

When you notice your transmission fluid runs out, you generally want to know the question: can I use motor oil for transmission? The simple answer is no. For optimum functionality, transmission fluid, and motor oil are essential for your vehicle engine system.

Transmission fluid and motor oil are two different products and perform several jobs. These two fluids have particular similarities. Though both fluids have similarities, you cannot use motor oil for transmission.

In challenging situations, you can use a small amount of motor oil for your transmission. However, just read this article attentively to know more important information about this topic.

what happens if you put motor oil in the transmission by mistake

Motor Oil

Motor oil can mainly lubricate the parts inside the motor. Additionally, motor oil contains various additives that create an excellent lubricant.

Without lubricants, more additives like anti-wear and tear, detergents, viscosity-related additives, antifreeze additives, etc. All of these additives work to keep the engine clean, protected, and calm.

Transmission Fluid

Accordingly, transmission fluid comes to lubricate your car’s transmission to provide fantastic performance. Moreover, this transmission fluid allows simple engagement of your gears and clutches.

The reason we have explained is that many people always spoil both for each other. There are two types of transmission fluid, as you know. The two types are automatic and manual transmission fluids, but in composition, these two fluids are similar.

Most importantly, as base oil, transmission fluid contains easter and crude oil. Typically, like motor oil, these fluids also contain additives.

Basically, manual fluids are much heavier than automatic fluids. Both types of fluids play a significant role in ensuring smooth gear shifting. Usually, transmission fluid helps to lubricate your gearbox parts and prevents wear.

From the above, we know that both fluids have one typical role: and this is that both of them can lubricate your parts. In particular, as a general rule, you cannot put motor oil for transmission fluid.

Why Does Transmission Fluid Look Like Oil?

Usually, the transmission fluid’s physical color and look are brown or red. Like oil, transmission fluid is also slick and thick. After that, to know if the transmission fluid is healthy, you can check.

Subsequently, red or pink color transmission fluid is healthy. On the contrary, black and brown color transmission fluid is dirty fluid.

Can Motor Oil Ruin A Transmission?

Yes, if you use motor oil in manual transmission, your manual transmission system will ruin. Nevertheless, if you are talking about motor oil, its main job is to develop the sealing and prevent rust. From any sludge, it also can protect your engine parts.

Even motor oil can cool down the car’s engine system. And finally, it can decrease the friction from your engine system. In contrast, transmission fluid works to help develop the performance of your manual and automatic transmission.

What Happens If You Put Motor Oil in the Transmission by Mistake

When using motor oil in your transmission fluid, you can face a few problems. The seriousness of damage depends on how much oil you put into your transmission. Also, it depends on how long you have been riding your vehicles with the wrong fluid.

Here are some essential things that will occur if you have put excess motor oil in a transmission.

Hear Some Noises

When you drive your car, you can hear noises if you put the wrong fluid in your transmission. So, before using the motor oil in your transmission, you should keep in mind this matter.

The gear Won’t Work

When you are in gear, it may not work correctly. The equipment will not respond appropriately after using the motor oil in your transmission. In addition, if you’re trying to reverse or drive your transmission, you can’t do that. It’s because motor oil properties won’t work like transmission fluid.

Experienced In Gear Slipping

You may have serious safety problems if you see your transmission in a sleeping mood. It would help if you had to repair and fix this problem immediately. Yet, no one wants to deal with gear slipping.

Burning Smell

If you smell like burning in your car, your transmission has an overheated fluid. Though you can find many causes for a burning smell, it will also occur if you put motor oil in the transmission.

Likewise, it will occur because transmission fluid has a high lubricating property. Generally, this property can prevent any destruction in between the engine parts. So, if you can’t properly lubricate your transmission system and use the wrong fluid, your system will be damaged.

Grinding Sensation In Gear

Due to the proper transmission fluid, your automatic transmission system will operate properly and smoothly. Unfortunately, if you use the wrong oil-such as motor oil, your transmission system will face nasty things.

As a result, you may feel shaking or grinding movements during the gear change. It will occur because of damaging your seals or O-rings.

Can I Use a Small Amount Of Motor Oil In Transmission?

Eventually, if you use a half quart of oil in the transmission, your car will be okay. In fact, you can not notice any significant damage to your vehicle. In general, you need to flush this oil immediately.

If you used motor oil and didn’t take any chances, it would help. For instance, if you use a small amount of motor oil and aren’t driving, it cannot cause damage. But you should take out this oil from your transmission immediately.

Why Should You Not Use Motor Oil For Transmission Fluid?

Using motor oil for your transmission is a worse idea. As mentioned above, though they have some standard functions, these fluids have different compositions. That is why putting motor oil might not be a safe way because of additives.

Since motor oil contains higher viscosity than fluid when you drive your car, meaning motor oil is slightly thicker than fluid. In other words, using it for transmission fluid reduces gear-shifting performance. Even so, you can hear some disturbing sounds from the bearings.

In worst cases, when in gear, there is a possibility that your car doesn’t function perfectly. Most importantly, it can lead to dangerous situations, so avoid using engine oil for transmission fluid.

Does Transmission Fluid Mix With Motor Oil?

Actually, you can mix them. Many people use a bit of motor oil in transmission fluid because they believe it benefits the engine.

Moreover, they also believe that if they mix the engine oil, it can clean the engine. Notably, if you mix too much engine oil, you should change it as soon as possible to prevent any problems.

The Differences Between Motor Oil And Transmission Fluid:

There are many differences between transmission fluid and motor oil. For example, the viscosity rate, life span, consumption rate, color, and detergents differ from engine oil. Furthermore, their purposes also are different from each other.

Below we are trying to break down the answer to these common questions: Are transmission fluid and motor oil the same? Indeed, below here, we also depict the differences between them.


The first visual difference between motor oil and transmission fluid is mostly color. Typically, transmission fluid color is dark red or green, while transmission fluid is red and manual fluid colors are dark green.

Consequently, the motor oil color is translucent with a golden hue or yellow. Over time the motor oil viscosity will break, and the color is getting darker.

Oil Change Interval

Motor oil and transmission fluid are both affected by time and mileage. Usually, you can drive your vehicle with transmission fluid between oil changes up to 30,000-60,000 miles. Comparatively, you should change your motor oil 3,000-6,000 miles. In reality, transmission oil lasts longer than motor oil.

Application Or Purpose

Though both oils (motor oil and transmission fluid) are lubricants, their application or purpose is different. Mainly, transmission fluid comes to lubricate your transmission system.

Correspondingly, the motor oil primarily lubricated the engine’s moving parts. We know motor oil offers exceptional engine protection against regular wear and sludge. Above all, three different motor oils are on the market, conventional synthetic, and semi-synthetic.

Transmission fluid vs. Engine oil

TypesTransmission FluidEngine Oil
FunctionRegardless, these fluids function majorly in the transmission system of your car. Similarly, it ensures clutches and smooth gears operation within the transmission system.Engine Oil operating in your engine system helps remove high friction between moving tools. In other words, it also provides a sludge and rust-free transmission system.
Rate Of ConsumptionWith mileage or time, transmission fluid doesn’t much reduce. More importantly, the matter is that it’s not typical for subjects to have low transmission fluid levels within a short time. Mainly, if you understand this, you should immediately check your system for any leakages.
Due to mileage and time, motor oil decreases. Always check your motor oil before riding your vehicle.
ColorMost transmission fluid’s color is red.Surprisingly, the engine oil color usually matches a bright yellow or golden color when unused. Practically, it turns black after using this fluid.
LifespanYou do not need to change this type of fluid regularly. The reason is that transmission fluid stays longer between oil changes.      To repeat, you should change your engine oil every 3000-6000 miles; it will increase depending on your oil type. Please don’t put the motor oil in your engine for a long time because it can lose its properties. That’s why make sure you change your oil on time.
DetergentsOn the other side, these fluids come with high detergents. And the son is that they operate in a different polluted environment.This oil contains a fair number of detergents.
Viscosity Generally speaking, this oil is highly viscous and comes to work under high pressure and temperature.  It’s a low viscous fluid formulated to work under low temperature and pressure.
small amount of motor oil in transmission

Fixing Problems Caused By Motor Oil on Transmission Fluid

Finally, if you notice any of the above problems or anything unusual, fix these problems by following the below steps. Depending on your range of damage, you need to fix your problem.

  • Flush the transmission
  • Refill the transmission
  • Make sure you use the proper fluid that matches your vehicle’s technology.
  • After doing the above steps, if you still face the problem, it’s best to go to the mechanic.


Q. What can I use instead of transmission fluid?

Mostly, the commonly used power steering fluid alternative is transmission fluid. Many manufacturers use automatic transmission fluid instead of power steering fluid.

Q. Where do I put transmission fluid?

Look at the back of your engine, which is near the firewall. In most cars, the transmission is located with rear-wheel drive. Meanwhile, on vehicles with front-wheel drive, the dipstick is situated near the front of the motor. Ergo, you can put your transmission fluid in this place.

Q. Can engine oil leak into the transmission?

Yes, it can leak into the housing of the bell. Some riders consider the bell housing transmission. But the transmission fluids don’t intermingle as fluid is sealed into the center where the gears are.

Final word

Ultimately, this is the guide where you can find the answer to the question: can I use motor oil for transmission fluid? In summary, putting a few motor oil for transmission fluid won’t bring extensive damage if you change it quickly.

Overall, both of these oils are distinct and come for different purposes. For that reason, you should avoid mixing motor oil with transmission fluid.

Apply proper liquid in your car and avoid unnecessary problems. If possible, always follow the manual transmission fluid that’s recommended.


I am Engr. Z Eusuf Lubricant Specialist, Mechanical Engineer & has been working with engine lubricants for a long time and knows what makes them work best. I can help you find the right oil for your needs, and I have tips on how to keep your engine running at its best.