If you are familiar with vehicles, you might have heard about transmission fluid. Generally, transmission fluid is used in vehicles for different purposes. This fluid works both as hydraulic fluid and lubricant. But transmission fluid is not the same as oil.
However, you might have seen bubbles in the transmission fluid. So, you might be confused about the fluid bubbles. Knowing details about transmission fluid and how the bubbles form is important. Moreover, you also have to know the reasons behind forming bubbles if you are supposed to drive a vehicle.
What is transmission fluid bubbles? What does foamy transmission fluid mean?
Transmission fluid bubbles are air bubbles formed in the transmission fluid. When air is introduced to the fluid or air enters through the filter, it becomes foamy transmission fluid. Moreover, improper balance of air and fluid, leaks, wrong oil, etc., might induce bubbles in the transmission fluid.
Whenever you notice a foamy transmission fluid, it means overfilling the transmission fluid. Sometimes, low transmission fluid also causes foaming of the fluid. That means foamy transmission fluid indicates too low or too full transmission fluid. Moreover, other mechanical problems might induce bubbles in the transmission fluid.
Bubbles also form when there is air in the transmission fluid. Whenever the transmission fluid comes close to the air or air enters through the filter, it will create bubbles in the transmission fluid.
Many other reasons are also responsible for automatic transmission fluid bubbles. For example, if there is leakage between the gasket and seals, it might induce bubbles in the transmission fluid. Moreover, contamination of transmission fluid can cause bubbles.
Generally, bubbles in the transmission fluid indicate something wrong in the transmission. If a necessary step is not taken, catastrophic failure might occur.
If you notice tiny bubbles in the transmission fluid, it is pretty normal. But if the bubbles are large, it will indicate problems. Most commonly, you might be driving with an improper fluid level or excessively full transmission oil.
An improper fluid level can cause different problems. For example, you might experience the jerking of the car when braking. Besides, when you change the gear range, you can notice a display of jolts and kicks. So, you should know the process of removing bubbles from the transmission fluid.
What causes bubbles in transmission fluid?
Bubbles in the transmission fluid can be normal if the bubbles sizes’ are tiny. But large bubbles or foamy transmission fluid can be induced for various reasons. So, let’s see what causes bubbles in transmission fluid.
A common reason for forming bubbles in the transmission fluid is air entrapment. Generally, when the fluid comes close to air by any means, air will enter into the fluid and form bubbles. Moreover, sometimes, the air is entered into the fluid through the filter.
Improper fluid level:
The most common cause of bubbles in the transmission fluid is improper fluid level. When the fluid and air balance are mismatched, bubbles can form in the transmission fluid. Improper fluid level indicates too much fluid or too little fluid.
Sometimes, overfilling the transmission fluid will induce bubbles in the fluid.
Leakage in the gaskets and seals is another reason for producing bubbles in the transmission fluid. Generally, when there is a leakage connected to the transmission fluid, it will cause air to pass through the fluid. This air will form bubbles.
Mixing different fluids:
Sometimes, people mix two or more different fluids together. This will cause combustion or chemical reactions between fluids. You might know chemical reactions release or absorb heat. So, bubbles will also produce from the heat released by the reactions.
Contamination in the transmission fluid will also cause bubbling in the fluid or foamy transmission fluid. A lousy transmission filter will induce contamination to the fluid.
Some other reasons might also be responsible for forming bubbles in the transmission fluid. For example, using the wrong type of transmission fluid, failure of transmission filter, etc., can also be responsible.
Should transmission fluid have bubbles?
Transmission fluid should not have bubbles. Sometimes, tiny bubbles might appear in the transmission fluid like most other fluids. These tiny bubbles are normal and will not cause any problem driving the vehicle.
But if the bubbles are large and dense, they indicate something wrong in the fluid or parts of the vehicle. Sometimes, bubbles in the transmission indicate mechanical problems of the vehicle. So, transmission fluid bubbles are not normal all the time.
Sometimes, bubbles in the transmission fluid will cause clogged transmission vents and other component failures. Moreover, it will affect the overall performance of the vehicle. So, transmission fluid should not have bubbles.
What happens if you get air bubbles in your transmission fluid?
You might not notice bubbles in your transmission fluid randomly. Whenever you got a problem in the vehicle, you might check different parts and notice bubbles in your transmission fluid. But different problems might arise if your transmission fluid has bubbles.
If you get air bubbles in your transmission fluid, it might cause catastrophic damage to your automatic transmission. Sometimes, you might experience jerking of the car while driving. Moreover, you will also experience it while changing different gear states.
Besides, bubbles in the transmission fluid will also induce friction in the transmission component and reduce the efficiency of the vehicle. The effectiveness of the transmission fluid will also be reduced.
Moreover, it can cause strange noise, overheating, contamination, fluid leakage, etc., problems in the vehicle.
How to get bubbles out of transmission fluid?
Now that you know bubbles in the transmission fluid can harm different components of your vehicle, you might want to remove the bubbles. So, let’s see how you can get bubbles out of transmission fluid.
- First, you have to stop driving the car and let the car rest for some time.
- Then you have to check the transmission fluid level whether it is too full or too low.
- If you see that the fluid level has passed the red mark that means there is a fluid overflow.
- To solve fluid overflow, you have to remove the excess fluid.
- If you see that the fluid level is pretty lower than the red mark that means there is a low level of fluid.
- Then you have to investigate where the fluid is going (there can be leaks or chemical reactions).
- If you can resolve the leakage, you should seal the leakage immediately.
- But if you can’t find the leakage or reason for finishing transmission fluid, you should seek professional help.
- If you can ensure that the fluid transmission fluid has bubbles, you should not drive the vehicle without solving the problem.
How to check transmission fluid with bubbles on a stick?
Checking transmission fluid is pretty essential because it can reduce many problems. You might don’t know how you can check the transmission fluid. So, let’s see how you can check transmission fluid with bubbles on a stick.
- Stop driving the car and park it on a straight surface for some time.
- Start the engine with an engaging parking brake.
- Keep the engine running for some time and you have to check the fluid level while the engine is running at the normal state (If the brand is Honda, you need to check when the engine is cold and not running).
- Then you have to find out the dipstick that might have a red, pink, or yellow handle.
- After finding out the dipstick, you have to pull it out.
- You have to pull out the dipstick with a clean piece of cloth or rug.
- Wipe the dipstick with the clean cloth and place it back in the reservoir.
- Remove the dipstick again and notice the indication on the stick whether it is full or low.
- If the dipstick indicates full, you have to replace the dipstick.
- But if the dipstick indicates low, you can refill fluid from the nearest auto center.
- If the dipstick indicates a burnt smell, that means there is a serious problem that should be solved immediately.
- Follow this process to check the transmission fluid level every six months.
Transmission fluid is one of the essential fluids that serve multiple purposes. Bubbles in the transmission fluid are normal sometimes. Sometimes, transmission fluid bubbles indicate something dangerous. Several reasons might be responsible like leakage, improper fluid level, contamination, etc.
I am an automotive enthusiast and have been interested in cars since I was a little kid. I have worked in the automotive industry for many years and have extensive knowledge of vehicles and their engines. I am a father of two and I love spending time with my family.
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