As a part of a routine maintenance schedule for your car, truck, or SUV brake fluid replacement is most often overlooked. Brake fluid has a certain useable life. This useable life is determined by the amount of water that the fluid absorbs. As brake fluid absorbs more water, its ability to do its job of stopping your car is greatly diminished.
Most owners’ manual will specify that brake fluid should be replaced either every year or every other year. I suggest that the brake fluid be replaced on all vehicles once a year. Many cars on the road today still have the original brake fluid in them. Over the years, this fluid absorbs a significant amount of moisture. As the moisture level of the fluid rises, it becomes more and more likely to boil over under hard braking applications. If the fluid boils, your stopping power will be non existent. Fresh brake fluid has a high boiling point and will help assure you that you cars braking system will work when needed the most.
To begin flushing your brake fluid, you will need a few parts and tools. You will need a suitable replacement fluid for your car. Be sure to use a new bottle of brake fluid, and not one that has been sitting, open in your garage for years. You will also need a clear glass jar, some clear vinyl tubing in a small inside diameter, some small wrenches, and you may need a jack dependent upon your vehicle.
The method that will be used to change your brake fluid is known as gravity bleeding. This procedure is simple and only requires on person and no special tools. Gravity bleeding can not be messed up and will not allow any air to enter into the braking system. Gravity bleeding is simple, but more time consuming than other bleeding methods.
To begin, you will need to locate the brake bleeder on the brake caliper that you will begin on. You may choose to begin with any caliper, just make sure that you do all four calipers on the car. If your vehicle has rear drum brakes, you will need to locate the brake cylinder on the rear wheels and bleed from there rather than from the caliper which does not exist on a drum brake system. If your vehicle is close to the ground and you cannot crawl under it to locate the brake bleeder, then you will need to safely raise the vehicle with a jack and jack stands.
Once you have found the brake bleeder, remove the rubber seal and place the vinyl hose over the end. Place the other end of the vinyl hose into the glass jar. Find a suitable wrench to open the brake bleeder. Slowly open the bleeder and the fluid should begin to drip or run out. The fluid will come out very slowly because it is only being forced out by gravity.
You will now need to monitor the brake fluid level in the brake reservoir located under the hood. Do not let the brake reservoir run empty. Continuously add more fresh brake fluid as the level drops. On average, each caliper or brake cylinder should be left open for about 30 minutes dependent upon flow. You are flushing the system until clear, fresh brake fluid runs out of the vinyl tubing.
Once the fluid runs clear, close the bleeder screw and snug it with the wrench. Do not over tighten. Remove the vinyl tubing from the bleeder and proceed to the next caliper or brake cylinder. Once you have completed all four corners, check the brake fluid level and adjust accordingly. Go inside the car and start the engine. Pump the brakes a few times and drive slowly down the street. Test the braking system to make sure that it functions as expected. The job of flushing your brake fluid is complete.
Brakes are the most important safety aspect of any car and should not be overlooked. A little preventative and routine maintenance will keep your car running like new for years to come. Please follow along with my other articles on routine maintenance for your car, truck, or SUV. Most routine maintenance is simple and can be done at home saving you hundreds of dollars over dealership costs.