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It’s no secret that when you’re in a pinch, it can be tempting to use something other than what the manufacturer recommends. You might have read somewhere online that transmission fluid is okay for brake fluid and you wonder if it’s really true.
Transmission fluid is designed to lubricate gears while brake fluid is designed to stop them from moving. They are both hydraulic fluids but they function differently.
Can You Use Transmission Fluid For Brake Fluid?
The answer is no. Transmission fluid and brake fluid are not interchangeable because they are made of different materials. So using transmission fluid for brakes can cause a lot of damage to the braking system. The two fluids have very different chemical compositions and boiling points, which means that it is essential to keep them separate from each other at all times.
Brake fluids are designed to stay stable even under very high heat conditions. There are many brake fluids like DOT-3, DOT-4, etcetera. All of them contain extra silicon materials. Where is the advantage of that?
The silicon materials can absorb the heat when the brake system comes to the boiling point or any extreme heat condition. That is why they are suitable for a brake job. On the other hand, transmission fluids are also friction modifiers. But due to some different mixtures, they cannot sustain any extreme heat.
Suppose you are in a desert and run out of brake fluids or need some of them. After some time, an idea comes to your mind of using some transmission fluids into the brakes.
When you put the fluids into the brake, you will notice that it does not last even a minute. It is because the fluid could easily burn in the range of 280 to 300-degree Fahrenheit. Even you ignore the heat, you will notice smoke when the temperature reaches to 400-degrees.
Transmission Fluid and Brake Fluid
Transmission fluid is like a lubricant to the moving parts of the engine. It also serves as both hydraulic fluid and oil. What’s a hydraulic fluid? It helps to cool the transmission and facilitates the gear shifts by lubricating the parts of the engine. Typically, these fluids are made from crude oil.
Brake fluids are used in the hydraulic brake and clutches. It helps to transfer the force of your pedal into pressure to the rear brakes. Whether your brake is working correctly or not is ensured by these brake fluids. It is because it reduces the friction between metals and removes junk.
What Would Happen After The Substitution?
The first thing you will notice after adding the wrong one is smoke coming from the brake system. The mixtures of the transmission fluids will deteriorate the whole brake system. Mainly, transmission fluids are petroleum products, and brake fluids are not. It makes a massive difference to their property.
When the heat is passed to the fluids, it will crumble the seals and also the moisture. These moistures will cause pitting and rust in the brakes.
When the seals are swollen, they block the passage of the brakes. It is essential for the proper functioning of the brake system. Sometimes the brakes get locked if you use transmission fluids. It is because the fluids can also expand and do not return to the reservoir.
Then the passage of the brake gets blocked after going a short distance. Again, petroleum products are heavier than brake fluids. That is why they don’t get mixed with the contaminant of brake fluids left in the system. Then, the damages have come to an immediate effect.
Let Brake Stay Without Fluid?
This is also not a good idea. When you have noticed the lacking of brake fluids, you should not leave it that way. It is because the brake will not function properly without these fluids. You already know the importance of these, right?
When you leave the brake in this condition, it might get jammed. Even some noises can also be noticed. You would see the brakes are overheated and not cooling down. Therefore, the brakes should not stay idle without the fluids.
What Can You Do?
Whatever you do, just do not mix the wrong fluids into the brakes. Suppose the mistake is done already. Then what? It would help if you immediately replaced the fluids. Make sure that there is no residue left in the brake system. Please wash them with soap water.
You can also go to a repair center if there are no shops around to buy some of them. Another common mistake is to choose diesel. We would say to stop thinking about it. Find out a better alternative option for such emergencies.
Soap water or detergent water is the best solution you can come up with. The solution is straightforward to make and use. It is crucial to mix the solution properly. The optimum ratio of detergent and water is 40:60.
First, you have to remove the old brake fluids before introducing a new substitute to the engine. That is because the alternative solution can have adverse effects on the braking system. Then you have to add the solution just like normal fluids. It would be best to use the brakes sparingly.
The reason is to avoid overheating issues. Overheated salt water would be a problem for the seal and brake passages. Therefore, you cannot run the car at a long distance. Several breaks are necessary to avoid the overheating problem.
When you go to near a repair shop, you can flush out the solution. If the solution remains a long time in the brake system, it could damage the system. But remember, this solution should be applied when you have run out of options.
The discussion topic was the question, “can you use transmission fluid for brake fluid?” After reading the article, you should get the idea of it.
This is not a good idea to use transmission fluids as a replacement. We have tried to bring out all the points about its harmful effects. If you are in such bad condition, you can use a soap water solution as an alternative.