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The answer is yes; you can use DOT 4 brake fluid in your DOT 3 system. However, it’s not always the best idea. DOT 4 brake fluid has a higher boiling point than DOT 3; however, it will not affect your DOT 3 system. You should, however, not use DOT 5 with DOT 3 or DOT 4 systems, as this is entirely different. You can use DOT 5.1 with DOT 3 or DOT 4, though.
What is Brake Fluid?
Brake fluid is a lubricant used to stop or slow down the movement of a vehicle’s wheels when it encounters friction. It helps reduce friction between the brake pads and the surface of the brake disc. It also reduces wear on the brake pads and rotors by reducing their contact with the discs.
There are several different types of brake fluid:
DOT 3 – This brake fluid has a long shelf life and is also used in some motorcycles. It is made up of anti-freeze, ethylene glycol, water, etc. DOT 3 can be used in cars and motorcycles because it does not require much heat to work properly.
DOT 4 – This type of brake fluid can only be used in cars because it requires high temperatures for its ingredients to be effective at stopping the vehicle.
DOT 5 – This is a silicon-based fluid and is hydrophobic. This means it does not mix with water. Therefore, any moisture that comes into the brake system will not mix with the brake fluid. Hence, all moisture will freeze or boil, thereby causing brake fade.
DOT 5.1 – This brake fluid is ideal for hydraulic clutch and brake systems. It has a boiling point of 260 degrees Celcius and a wet boiling point of 180 degrees Celcius. This brake fluid is perfect for ABS systems because of its low viscosity.
Here’s a quick video to explain the different brake fluids.
Are DOT 3 and DOT 4 Brake Fluid Compatible?
DOT 3 and DOT 4 work similarly; the only difference is their boiling point. They also contain different additives to make them more resistant to freezing during cold weather. You can use DOT 4 in your DOT 3 system; however, it cannot be used vice versa.
What Happens if You Use the Wrong Brake Fluid?
Brake fluid is designed to help your brakes perform optimally. It contains additives that make the brakes work better, even if they get dirty or damaged. If you use the wrong type of brake fluid, however, those additives may not work as well, and your brakes will be less effective.
Using the wrong type of brake fluid could also damage your brake pads and rotors or even cause them to fail. This will cause additional wear on your car and can also cause other problems if you have a car that uses drum brakes instead of disc brakes.
Can You Mix DOT 3 and 4?
Yes! You can mix DOT 3 and 4. The reason being both fluids are glycol-based. However, if you have a DOT 4 system, you should avoid filling it with DOT 3.
How Does Moisture Affect Braking Performance?
When you apply the brakes, your vehicle will generate friction to slow down. The friction that is generated depends on how much moisture is in your brake fluid. A wet brake pad creates more friction than a dry pad, which results in poor braking performance. In addition, the difference between wet and dry brake pads increases with temperature.
The higher the temperature, the more moisture is created. This means that if you drive in hot weather or have recently washed your car, you may experience decreased braking performance if they are not completely dry. The critical thing to remember is that if your brakes are too wet or too hot, then they won’t work right because they’ll be too much resistance for them to handle properly.