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How Can You Tell When Your Brake Fluid Is Running Low?

brake fluid low

Brake fluid is a vital part of your vehicle’s operations, and it is often overlooked. Most mechanics and other experts suggest checking your brake fluid levels monthly at a minimum because it is so fast and simple to do with dire consequences possible if it runs low. There’s a reason for the adage “an ounce of prevention is worth a pound of cure,” and the regular inspection of your brake fluid to determine if your brake fluid is low is no exception. If you detect any problems like a brake fluid leak early on as they form, the risk of accidents from failed brakes is far lower. It is also easier on your pocketbook to address problems before they multiply. Follow these steps to check for low brake fluid in your car or truck:

  • Locate the brake fluid reservoir. Usually, this is a plastic container with a screw-cap lid situated near the brake master cylinder on the driver’s side. In antique vehicles, however, the reservoir is often made of metal.

  • Pump the brakes repeatedly if you have an anti-lock brake system (ABS): Depending on the type of car or truck you have, the number of times you depress the brakes can vary, although 25 to 30 times is fairly standard. Refer to your owner’s manual, however, for the proper number for your vehicle.

  • Wipe any debris from the cap when it is still closed with a clean cloth: You do not want any grit accidentally making its way in to the brake fluid as you check it because there is the potential of dirt interfering with the performance of the seals on the master cylinder. If that happens, your brakes could fail.

  • Open the cap to the brake fluid reservoir: With plastic reservoirs, the cap simply screws off. For vintage metal varieties, however, you may need to pry it off with a flathead screwdriver or similar tool. Never leave the cap open longer than necessary, as it can introduce moisture into your brake fluid, which will cause it to chemically break down over time.

Check the level and color of your brake fluid: Your brake fluid is low if it does not reach an inch or two below the cap and may indicate a brake leak. Top the reservoir off with the type of brake fluid recommended in your owner’s manual and consult a mechanic immediately. Also note the color of your brake fluid. If it is dark, your vehicle may require a brake fluid flush and replacement.

This is how to regularly check if your brake fluid is low, but there are other, more serious signals that you should have your brake system inspected promptly. If you suddenly notice a change in the amount of pressure needed to depress your brake pedal or it goes further down than usual, you likely have a serious brake fluid leak. Also, most vehicles have warning lights that illuminate on the dash, so take heed if a Brake Warning, ABS, or similar icon suddenly shows up. If your vehicle exhibits these signs or you have found your brake fluid is low during your regular inspections, don’t hesitate to contact one of our mechanics for a consultation.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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