Supplies Needed

• 10mm Open End Wrench
• 8mm Open End Wrench (or adjustable Crescent Wrench)
• DOT 3 or other compatible Brake Fluid (32oz.)
• Floor Jack
• Jack Stands
• Empty Bottle
• Vinyl Airline Hose
• Turkey Baster or Other Fluid Transfer Device
• [Optional] Zip ties to hold the airline hose in place
• [Optional] Brake Fluid Bleeder Kit

When To Change Your Brake Fluid

Brake fluid absorbs moisture over time, which causes it to break down.  As brake fluid breaks down, the boiling point lowers.  This makes the brake fluid more susceptible to heat failure where the fluid boils and then you have no brakes.  In just a period of 2 years, I have seen a significant change in color and consistency.  It just so happens that many car manufacturers recommend changing your fluid at 2 year intervals.  While most people have experience with driving for many years on the same brake fluid, I am of the opinion that brake fluid is cheap and fresh fluid protects my brakes.

How To Do It

1. Uncover The Brake Fluid Reservoir

On a 2014 Toyota Sienna, you will find the brake fluid reservoir underneath a plastic cover right below the windshield, on the driver’s side of the engine compartment.  This cover has a tab that makes it easy to lift away with your finger.  Once this cover is out of the way, you have full access to the brake fluid reservoir.

2. Open The Brake Fluid Reservoir

After you remove the cap for the brake fluid reservoir, you will notice that there is a fine mesh filter in place to keep debris out of your brake fluid.  This screen also prevents you from being able to remove the old brake fluid.  You can remove the screen by simply lifting it straight up and then turning it counter-clockwise at the top of the reservoir.  With the screen removed, you now have access to the bottom of the reservoir and can pump out the old fluid.

3. Pump Out the Old Brake Fluid

You will need to pump the fluid out of the reservoir, as there is no drain.  Be careful handling the brake fluid as it is caustic and can damage any painted surfaces.  While I used a brake bleeder kit, powered by an air compressor, to pump out the old brake fluid, this can be done just as easily with a turkey baster or some other small liquid transfer pump.  You want to get as much fluid out of the reservoir as possible to reduce contamination of the new fluid.

4. Add New Fluid To Reservoir

With the brake fluid reservoir empty of old fluid, it is now time to fill it with new fluid.  Do not worry about overfilling the brake fluid reservoir, as you will be pumping this fluid down into the brake lines and will have to keep topping off the reservoir as you go.  This is my favorite part of using the Brake Bleeder kit. It comes with a useful bottle with a ball valve to prevent spilling.  The bottle can be inverted into the reservoir and as the fluid level drops and uncovers the end of the bottle, fluid flows out and keeps your reservoir topped off for you.  This kit even allows you to adjust the height of the fluid.  While this is a convenience, it is not a necessity.

5. Lift The Rear Of The Vehicle

The order of which wheels you work on first is basically arbitrary.  I like to start with the rear, because the largest amount of fluid that you need to flush goes through the lines to the rear wheels.  The jack point is a fairly obvious post right behind the muffler in the rear of the vehicle.  You can see my floor jack placed on it.  You only need to lift the rear of the vehicle high enough for you to reach the rear brake bleeder valves comfortable.  Make sure to use jack stands to support the car for safety.

6. Uncover The Bleeder Valves On The Rear Wheels

The bleeder valve is covered by a large rubber cap.  This cap can be easily pulled off of the bleeder valve.  The valve is located towards the top of the brake piston assembly at the rear of the wheel.

7. Connect Airline Hose To Rear Brake Bleeder Valve

Place your vinyl hose over the end of the brake bleeder valve.  You should route the hose up from the bleeder valve.  This guarantees that air bubbles will rise away from the valve and fluid will gather there.  If there is nothing suitable around, then a jack stand can be used to lift the hose away from the bleeder valve.  On the driver’s side of rear wheel this was the case for my 2014 Toyota Sienna.  On The passengers side, I was able to use the exhaust pipe, because it was cool.  If this was not the case, I would have used a jack stand again.  The other end of your hose should go into your container for storing old fluid.

8. Bleed The Rear Brakes

The rear brake bleeder valves are opened using a 10mm open end wrench.  You don’t need to turn the valve more than about 1/4-1/2 of a turn to allow brake fluid to flow.  Brake fluid likely will not start flowing immediately.  To push fluid out of the brake lines, simply push on the brake pedal.  After pumping the brakes a few times, check on the hoses to make sure that fluid is flowing.  If your fluid is sufficiently old, then the old fluid will likely be noticeably darker than the new fluid.

You may see clear fluid come out initially, since the fluid closer to the brakes is more insulated from moisture than the fluid in the reservoir.  The brake lines going to the rear wheels are fairly long.  To flush all of the old fluid out of the rear lines, you will probably need from 12 to 16 oz of brake fluid.

9. Keep The Brake Fluid Reservoir Topped Off

While you are flushing the brake lines, make sure that the brake fluid reservoir doesn’t run dry.  The brake bleeder kit that I use comes with a bottle with a ball valve for this purpose.  This is not required as long as you check the fluid level in the reservoir after every couple of pumps of the brake pedal.  The same effect could be gained using any inverted bottle with a small hole in the cap.  The valve helps to keep fluid from draining everywhere when you are done.

10. Close The Bleeder Valves

Once you start to see clear, new fluid coming out of the bleeder valves, the lines are flushed.  Close the bleeder valves, making sure that there is fluid in the hose to prevent air bubbles from entering the brake lines.  After closing the valve, pinch the end of the hose close to the valve and pull it off of the valve.  Pinching the hose helps keep the fluid in the hose from spilling everywhere.  If you spill brake fluid, be sure to clean it up quickly.  Make sure to replace the rubber cap on the bleeder valve to keep it from getting clogged or rusted.

11. Rinse And Repeat On The Other Side

Please note that while I describe this process only once for the rear brake lines, I suggest that you bleed the lines one wheel at a time.  After completing this procedure for one of the rear wheels, start over at step 6 for the other rear wheel.

12. Lower The Rear Wheels And Relocate To The Front

Once you have flushed both brake lines in the rear of the vehicle, lift the car off of the jack stands.  Remove the jack stands from under the rear jack points.  Now you are ready to lower the rear axle as the rear brake lines are flushed.  After the rear axle is resting safely on the ground, move your jack to the front, center lift point (consult your manual, if you don’t know where it is).  Always use jack stands at the vehicles side lift points when crawling under your car.

13.  Complete Steps 6 Thru 10 For The Front Brake

With the front wheels lifted enough for comfortable access under the vehicle, you can easily access the bleeder valves on both sides.  You can see the location of the bleeder valve towards the top of the brakes in the picture above, and the drivers side wheel in the picture below.  These bleeder valves use a very small wrench, 8mm to open the bleeder.  The procedure to flush these lines is exactly the same as for the rear wheels, but it will take about half as much fluid, because the lines are shorter.

14.  You’re done!

Now that you have flushed the fluid for all four wheels, you are done.  Just make sure that you have the brake fluid reservoir filled properly above the minimum and below the maximum level.  Replace the screen filter in the reservoir.  Secure the cap back on the fluid reservoir.  Return the dust cover.  Lastly, don’t forget to take your vehicle off the jack stands and close the hood. There is no break in period for the fluid.  If your brake fluid was extremely old, you may notice that your brake pedal feels firmer.  As for disposing of the brake fluid, Popular Mechanics recommends pouring it into a container with cat litter and just letting it evaporate.  Other sources say that you can dispose of it at oil recycling centers, but you might want to call ahead and ask.