How to Check Brake Fluid

By eHow Cars Editor

Check Brake Fluid Check Brake Fluid

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Check the brake fluid when you check all the other fluids. It's easy to do and only takes a minute.

Instructions

Difficulty: Easy

Things You’ll Need:

Step1
Find the brake master cylinder. This is usually located under the hood on the driver's side of the car, toward the back of the engine compartment. Imagine where your brake pedal would end up if it went all the way through to the engine. The brake master cylinder is a small (about 6-by-2 inches), rectangular piece of metal with a plastic reservoir and a rubber cap on top, and small metal tubes leading from it.
Step2
Check your manual if you aren't sure that you've found the master cylinder. The rubber cap will usually read "use only DOT 3 or 4 brake fluid from a sealed container."
Step3
Note that on most newer cars the reservoir is translucent and you can see the fluid level without removing the cap. There will be a "full" line, the brake fluid should be at this line.
Step4
In older cars (pre-1980) the brake master cylinder reservoir may be made entirely of metal so that you must take the top off to check the fluid level. The top is held on by a metal clamp, use a screwdriver to pop off the clamp and lift the lid.
Step5
Add brake fluid to the "full" line. Use the correct brake fluid for your car: Check the rubber cap and your owner's manual to find out what grade of brake fluid your car requires. Most cars use DOT (Department of Transportation) 3 or 4. If the reservoir has 2 parts, fill both halves.

Tips & Warnings

  • If the brake master cylinder is empty, the brake pedal will go to the floor. If this is the case, you will have to bleed the brakes in addition to adding fluid: Time to see your mechanic, who will flush and refill the braking system.
  • Brake fluid is very toxic. Keep it away from hands and eyes, and avoid spilling it on the ground. Dispose of empty containers carefully. Be especially careful not to spill brake fluid on your car's paint.
  • Wash your hands well after handling brake fluid.
  • Don't drive a car that has run out of brake fluid until bleeding the brakes.

Comments

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Anonymous

Anonymous said

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on 7/9/2006 Many newer automobiles and trucks will set the brake warning light when your fluid is low. Adjust the fluid level and see if the light goes off (and stays off). Still, inspect the brakes though, even if the light does go out; there's a reason why the fluid is low.

Anonymous

Anonymous said

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on 3/14/2006 Color is not an accurate indication of the condition of your brake fluid. Make sure your mechanic uses a creditable method for testing the condition of the brake fluid.

Anonymous

Anonymous said

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on 11/22/2005 If brake fluid is exposed to moisture for too long it will lose it's effectiveness.

Anonymous

Anonymous said

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on 11/22/2005 Brake fluid can absorb water very quickly, as the braking system is not airtight. Bleed and change every 12 months or every 30,000 miles (whichever comes first). Not every three years, especially if you live in a cold climate.

Anonymous

Anonymous said

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on 11/22/2005 Low brake fluid in the master cylinder may be a sign that your brakes pads or shoes are starting to wear out. As they get worn, the wheel cylinders expand and suck brake fluid out of the master cylinder. Don't assume that all you need is extra brake fluid! Have your brakes checked and get a mechanic to tell you how much percentage of pad or shoe you have left.

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eHow Article:  How to Check Brake Fluid

eHow Cars Editor

eHow Cars Editor

Category: Cars

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