Brake fluid is typically light yellow, as reported by experts and vehicle owners. However, the color may change to brown as it ages, depending on the manufacturer and usage of the vehicle. You may find brake fluid under your car near the wheel well in case of a leak.
Maintaining your vehicle’s brake system is crucial for ensuring its longevity and trouble-free operation. Keeping track of the color of your brake fluid is essential, although it generally takes a few years for the brake fluid to deteriorate when the brake system is used correctly.
Knowing your vehicle’s brake system and fluid helps you recognize when you need to replace the brake fluid. Moreover, it is worth noting that brake fluid color varies depending on the type of brake fluid used.
Factors contributing to brake fluid’s color change include regular heating, aging, banging rubber brake lines, and moisture. Therefore, keeping track of your brake fluid color and getting it replaced when necessary is vital for maintaining a safe and reliable vehicle.
Brake Fluid Color Guide
To replace your master cylinder or brake pads, investing in a bottle of brake fluid is recommended. Four brake oil types are available: DOT 3, DOT 4, DOT 5, and DOT 5.1.
These brake fluids are identifiable by their unique colors. DOT 3, DOT 4, and DOT 5 brake fluids share the same color and will turn brown as they age. The color of brake fluid can also change due to factors such as regular heating, aging rubber brake lines, and moisture.
DOT 3
The poly glycol-based DOT 3 brake fluid was one of the initial brake fluids to be utilized, but it has become less popular with the introduction of more advanced options. Its minimum boiling point is 205°C, with a wet boiling point of 140°C.
Depending on the climate and operating conditions, DOT 3 brake fluid can absorb one to two percent of water. It is the recommended option for domestic cars and light trucks.
DOT 4
Another type of brake fluid is DOT 4, which is poly glycol-based. Its dry boiling point is 230 degrees Celsius, while its wet boiling point is 155 degrees Celsius. This brake fluid is suitable for modern vehicles of medium and high sizes. DOT 4 is recommended for cars with ABS systems, towing capabilities, high-speed braking systems, and those driven in high altitudes.
DOT 4 brake fluid is also prone to absorbing moisture, which can reduce its effectiveness in the long run. Additionally, it can damage the paint on the vehicle, so it should be handled with care. The color of the DOT 4 brake fluid is clear with a slight yellow tint.
DOT 5
DOT 5 is a popular brake fluid that is based on silicone. It has a dry boiling point of 260°C and a wet boiling point of 180°C. DOT 5 is used in military, antique, and weekend collector vehicles that sit long. However, it is incompatible with DOT 5.1, DOT 4, and DOT 3 brake fluids.
The good news is that DOT 5 brake fluid is safe for your vehicle’s paint and does not absorb water. It also works well with rubber formulations. But, it does absorb air, which may result in a poor pedal feeling. As a result, it is not recommended for racing cars as it becomes compressible at high temperatures.
Water and DOT 5 brake fluid do not mix well. Water entering the DOT 5 brake fluid may cause gassing, freezing, and severe localized corrosion. DOT 5 brake fluid is not recommended for ABS, as it may cause foaming and aeration leading to a spongy brake feel.
DOT 5.1
The DOT 5.1 brake fluid is another poly glycol-based fluid that has gained popularity due to its superior performance. With a minimum dry boiling point of 270°C and a wet boiling point of 190°C, it is suitable for high-performance vehicles like race cars, towing vehicles, and delivery and fleet trucks. DOT 5.1 is also compatible with DOT 4 and DOT 3 brake fluids. Compared to DOT 4 and DOT 3, DOT 5.1 has a higher boiling point, making it an excellent choice for extreme driving conditions.
Although DOT 5.1 can absorb moisture from the atmosphere, reducing its boiling point, it is less susceptible to moisture absorption than DOT 3 and DOT 4. However, it would be best if you still handled it with care, as it can cause damage to the paint of your vehicle. The brake fluid is available in an amber color.
Frequently Asked Questions About Brake Fluid
Is brake fluid always blue?
No. Brake fluid is either clear, yellow, or blue.
Can a car run without brake fluid?
Indeed, it is possible to have brakes without brake fluid, but it will inevitably lead to brake failure or negative impacts on your car’s braking system. The hydraulic brake system relies on brake fluid to function correctly. Therefore, if your brake fluid level is low or non-existent, your car’s braking performance will be severely affected. It is crucial to refill the brake fluid reservoir to ensure the brakes can function correctly and provide the driver’s and passengers’ safety.
Is topping up your brake fluid easy?
Adding brake fluid to your car is a simple process. If your brake fluid reservoir has a small opening, it is recommended to use a small funnel to pour it into the reservoir.
Can I top up the brake fluid myself?
Indeed, you can refill your brake fluid yourself if it’s running low. Follow these simple steps to top up your brake fluid:
- Remove the cap of the brake fluid reservoir.
- Use a funnel to slowly pour in the brake fluid until it reaches the maximum level indicated on the reservoir.
- After adding the brake fluid, tightly screw on the reservoir cap to prevent leaks.
What color should brake fluid not be?
If the color of your brake fluid changes from clear with a slight yellow tint to dark brown or black, it’s time to replace your brake fluid with a flush as soon as possible.
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