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Signs and Causes of Low Brake Fluid

signs of low brake fluidOne of the most overlooked fluids in a vehicle is the brake fluid, although it really shouldn’t be. Brake fluid is a critical component in the hydraulic brake system and stopping would be quite the challenge without brake fluid. In fact, your brakes may not work at all if your brake system is low or out of brake fluid. Hydraulic brake systems require fluid to help increase pressure to stop a vehicle. 

Brake pressure builds up and begins forcing fluid to the brakes, forcing the pads to compress against the rotors that are attached to the wheel hubs spinning as the wheel turns. The high pressure created is what causes the car to slow down. If brake fluid is not present, the brake system will not be able to build up the pressure needed to stop the car. 

When the fluid begins to break down or a leak somehow occurs, the brake system’s function becomes much less effective. Here’s what happens if your car’s brake fluid is low: 

What Causes Low Brake Fluid

Brakes are the number one safety feature in your car. If your brakes are not working or the brake light suddenly comes on, there is cause for concern. The following are the most common reasons your brake system may be low on brake fluid:

  • A leak in the system – whether it’s located in the master cylinder, brake lines, hoses, or the calipers, a leak in the brake system can greatly reduce the hydraulic pressure required to slow and stop a vehicle. Leaks can be caused from something as simple as normal wear and tear to driver error from hitting something in the road while driving. Brake fluid leaks can most often be identified by residue left under the vehicle while parked or by checking the fluid reservoir located under the hood. 
  • Worn brake pads – When pads are worn down, the caliper piston is forced to travel farther to the brake pads, away from the housing. This requires more brake fluid to travel further down which may become depleted over time.
  • Damaged brake line – Many areas of the brake system may wear down due to age and use; however, some steel components in the brake system are prone to rust, especially in snowy climates where roads are often salted to reduce snow and ice.

Signs Your Brake Fluid Needs to Be Changed or Flushed

When brake fluid begins to break down from use or has leaked out, your braking experience may change. Pull over to a safe area, check your brake fluid level and quality, first. If the fluid doesn’t look right or something doesn’t feel right, have your vehicle towed to an automotive center for an immediate inspection. Do not attempt to drive the vehicle if the brakes are not functioning well. Do not put yourself or others’ safety at risk. 

  • Brake warning light illuminates – Most vehicles are equipped with brake sensors in the brake system that communicate with the car’s internal computer to alert the driver to any potential troubles. A low brake fluid level can trigger the brake light to come on. Because the brake system is completely sealed, brake fluid should remain close to full, however, some fluid loss is normal. If a significant amount of fluid is missing, have your vehicle inspected right away.
  • Low, discolored, or dirty fluid – Fluid that is any shade of brown or black or that has particles floating around indicates fluid is old and dirty. Low fluid may indicate there is a leak in the system, especially if it has been filled recently. Brake fluid leaks are serious as they provide little to no stopping power while driving. 
  • Hard to stop or mushy brake pedal – Low brake fluid can cause that spongy feeling in your brakes while you step on the brake pedal. This occurs due to a build-up of moisture in the brake system beginning to boil due to the incredible amount of heat created while braking. This also causes an increase of air in the brake lines. Unlike brake fluid, the air cannot be compressed and instead causes the brake pedal to go down further, reducing the car’s stopping ability. 
  • Brake replacement – If you replaced the engine in your car, you wouldn’t use spent oil from the old engine, right? The same applies to brake fluid. Any time the hydraulic system is opened up and exposed to the air, the possibility of contamination is high. By having any old brake fluid flushed out and replaced with fresh, clean brake fluid, you’re ensuring your brakes work to the very best of their ability and safeguarding yourself and others on the road from brake failure.  

Expert Brake Technicians

When it comes to your brake system, you want someone who is knowledgeable, experienced, and thorough. The Technicians at Sun Auto Service understand the importance of safety and work hard to ensure your brakes are in proper working order every time you visit a Sun Auto Service. That’s right! Even when you come in for an oil change, our Technicians will inspect your brakes as part of the multi-point inspection we offer with every oil change. Your safety is a priority to us at Sun Auto Service, take a brake and stop into any Sun Auto Service location for a brake inspection today!