The Role of Brake Fluid in Your Braking System

1. The Role of Brake Fluid in Your Braking System Introduction Your vehicle’s braking system is one of the most important safety features, and while brake pads and rotors often steal the spotlight, brake fluid plays a vital—yet often overlooked—role. It’s the lifeblood of your braking system, allowing force from your foot on the pedal to be transferred into stopping power. Without it functioning properly, your brakes can’t do their job safely. What Is Brake Fluid? Brake fluid is a type of hydraulic fluid that flows through your brake lines and allows your car to stop when you press the brake pedal. It’s specifically formulated to withstand high temperatures and pressures without boiling or freezing. There are several types of brake fluids, including: DOT 3– Most common, glycol-based DOT 4– Higher boiling point, common in newer vehicles DOT 5 – Silicone-based and not compatible with DOT 3 or DOT 4 systems Always refer to your vehicle’s manual to determine the correct type for your system. How Brake Fluid Works in Your Vehicle When you press the brake pedal, it compresses the brake fluid inside the master cylinder. This pressure is transmitted through the brake lines and hoses to the brake calipers or wheel cylinders. These then press the brake pads or shoes against the rotors or drums to slow down your vehicle. Brake fluid must remain incompressible and maintain its viscosity under a wide range of temperatures to ensure consistent performance and driver safety. Why Brake Fluid Degrades Over Time Brake fluid is hygroscopic, which means it absorbs moisture from the air over time—even through the rubber seals in your brake system. This moisture lowers the fluid’s boiling point, making it less effective under high-heat conditions, such as hard braking or mountain driving. Heat from braking also causes the fluid to degrade. Eventually, contaminated brake fluid can cause corrosion in brake lines and internal parts, risking total brake failure.

2. Signs Your Brake Fluid Needs Attention It's important to recognize early signs of deteriorating brake fluid: Spongy or soft brake pedal Longer stopping distances ABS warning light on dashboard Brake fluid appears dark brown or black instead of clear yellow Unusual noises during braking These symptoms can signal either contaminated fluid or air in the brake lines—both of which require immediate service. Brake Fluid Flush vs. Top-Up | What You Need to Know Topping up your brake fluid only adds fresh fluid to what's already there. It doesn't remove contaminants or moisture. A brake fluid flush, on the other hand, involves draining all the old fluid and replacing it with new, clean fluid. Most manufacturers recommend a brake fluid flush every 2 to 3 years or 24,000 to 36,000 miles, depending on driving conditions. Check your owner’s manual for specifics. Risks of Ignoring Brake Fluid Maintenance

3. Failing to change your brake fluid can result in: Brake fade: Reduced braking effectiveness Internal corrosion: Damage to brake lines, master cylinders, and ABS units Boiling brake fluid: Especially under heavy braking, leading to total loss of stopping power A simple fluid change is much more affordable than replacing an entire braking system or risking safety. How Professionals Check and Replace Brake Fluid Professional mechanics follow a systematic process when checking and replacing brake fluid to ensure optimal braking performance and driver safety. The inspection usually begins with a visual check of the fluid’s color in the reservoir. Fresh brake fluid is typically a clear to light amber color, while contaminated or aged fluid appears dark brown or even black, indicating the presence of moisture, debris, or internal corrosion. Mechanics may also use specialized electronic tools to test the fluid’s boiling point and moisture content, helping to determine whether a full flush is necessary. If the fluid is found to be degraded, a complete brake fluid flush is performed. The process begins with the technician extracting the old fluid from the master cylinder reservoir. Once emptied, fresh brake fluid is added, and the entire brake system is flushed—this involves bleeding each brake caliper or wheel cylinder to push the new fluid through the lines while forcing out all old, contaminated fluid and any trapped air bubbles. Proper bleeding ensures consistent hydraulic pressure and restores pedal firmness. After the flush, the technician tests the system for leaks and confirms smooth, responsive braking. This thorough approach ensures your brake system functions safely and reliably, especially under emergency conditions, and hence repairs the brake system. Brake Fluid Comparison Chart Brake Fluid Type Dry Boiling Point Wet Boiling Point Key Use Case DOT 3 205°C (401°F) 140°C (284°F) Standard passenger vehicles DOT 4 230°C (446°F) 155°C (311°F) Modern vehicles, performance DOT 5 260°C (500°F) Not applicable Specialty/silicone systems Conclusion Brake fluid may be out of sight, but it should never be out of mind. Regular brake fluid checks and flushes ensure your braking system works at peak performance when you need it most. Don’t wait for

4. signs of trouble—preventative maintenance keeps you safe and avoids costly repairs down the road. www.autonationservicecentre.com +16047060388 service@autonationservicecentre.com 1606 Clark Dr, Vancouver, BC V5L 4Y2, Canada