Video tutorial on how to replace the rear wheel cylinders on a 1st generation Toyota Tacoma. This particular truck I am working with here today is a 2001 4wd model which has the larger drum brake assembly. A similar replacement can also be applied to the 3rd generation Toyota 4Runner as well. The existing wheel cylinders were not seized or leaking on this truck, but thankfully the previous owner had new replacements just for preventative maintenance. Typically wheel cylinders can fail in a couple different ways. They can either seize up from rust, they have two pistons, one pointing to the front and the other towards the rear. Either of this pistons or both can seize. The seals can also fail in the wheel cylinder which would be shown by residue inside the brake drum assemble or on the outside of the backing plate towards the bottom.
- standard screwdriver
- hold down spring tool
- ratchet with sockets
- brake pressure bleeding kit
- brake fluid
- wheel cylinders
- rubber gloves
- line wrenches
- rubber hose
- drain pan
- brake fluid
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Step 1: Drum Removal
First start by safely elevating the rear of the vehicle and then remove the wheels. Now to remove the brake drum. Unfortunately the parking brake linkage at the drum, also known as the parking brake bell crank is seize and catching up on the lip of the drum. So I’m just using a hammer to retract the pads, this will be getting replaced as well and that will be saved for a future video. Once that drum is removed, the wheel cylinder is located at the top of the assembly.
Step 2: Wheel Cylinder Removal
The wheel cylinder can be replaced without completely disassembling the drum brakes.
Remove the “C” clip for the adjuster lever using a standard screwdriver and then remove the lever.
I found it’s easier to close up the automatic adjuster so the shoes have a little bit more movement. Depending on which side you’re working on, these do turn in different directions. You can use a screwdriver, pliers, or your fingers to rotate the star wheel adjuster.
Remove the shoe’s hold down spring, only one needs to be removed. Considering we will be working with brake fluid in a moment, make sure that fluid does not come in contact with paint as it can damage it.
Moving onto the backside, remove the brake line at the wheel cylinder. Use a line wrench to prevent the line fitting from stripping. Unfortunately I was having a slight problem here as the fitting is rusty enough to twist the line slightly. Once this happens, the line’s structure is jeopardized, therefore they will need to be replaced regardless if it breaks or not. Have a drain pan blow to catch the dripping fluid.
Remove the two 10mm bolts which holds on the wheel cylinder. These are in rough shape, so they’ll be replaced with socket heads of a higher grade instead.
Give the wheel cylinder a light tap with a hammer if it’s stuck in place and then remove.
As you can see the wheel cylinder is still functioning fine. However after disassembly, I did notice a bulge in the one boot which is cause by rusting. This will eventually cause an opening, forcing foreign contaminants around the piston, causing that piston to seize.
Step 3: Wheel Cylinder Installation
Install the new wheel cylinder. I have installed new fasteners with washers as well, but you can reuse yours if they’re still in good condition.
Reinstall the hold down spring for the shoe. Also make sure those shoes are properly interlocked with the wheel cylinder’s pistons. The shoes should fit inside the U shaped push blocks. And then reinstall the automatic adjuster lever, along with the “C” clip. I’ll show you how to adjust the shoes once the system has been bleed.
Step 4: Replacement on the Opposite Side
Moving onto the driver’s side of the truck.
Remove the “C” clip for the automatic adjuster lever.
Then remove the lever.
Close up the adjuster.
Remove the brake line on the rear and have a pan handy to catch any dripping fluid. Most of the fluid was drained from the opposite side here so I didn’t really have any fluid left for this side. Unfortunately with this side, the fitting was too far gone so I just the line off.
Install the new wheel cylinder.
Reinstall the hold down spring for the shoe.
Then reinstall the automatic adjuster lever and “C” clip.
Step 5: New Rear Brake Lines and Rust Clean Up
I took the easier, but slightly more expensive route and purchased new pre-bent lines from the dealer. While they are more money, they do have an epoxy coating to resist rusting and a rubberized casing as added protection.
Due to rusting, some of the bolts used to hold down the existing lines did break, so the remaining studs needed to be drills and then the threads were cleaned up using a tap. While the brake lines were off, I stripped down the rest of the axle, treated the rust and then applied some farm equipment paint.
As you can see I now have the new pre bent lines which are getting installed.
All the new hardware bolts are switched out to stainless steel so I don’t need to worry about future rusting. I did purchase new retaining clips for the brake lines, just waiting for them to arrive. While the lines are hooked up, I can still bleed the system of air. Ensure all the fittings are tight.
Step 6: Setting Up the Pressure Bleeder
Here I’m using my pressure bleeder kit. I have been using this pressure bleeder for replacing the fluid in my other car and it makes brake work a breeze. No need to have an extra helping hand and it efficiently bleeds the system without any issues. Included in this kit is the pressure bleeder tank, supply line, and generic master cylinder reservoir cap which we’ll be using.
Start by removing the orange cap which also has the pressure relief valve. I added about 1 litre or quart of brake fluid. This truck requires a DOT 3 fluid type. You’ll want to ensure the bleeder has enough fluid so it doesn’t run empty and risk the chance of introducing air into the system.
Step 7: How to Bleed the Brake System of Air
Open the hood and locate the master cylinder’s reservoir which is mounted on the firewall on the driver’s side. Wipe off the surrounding around to remove any dirt which can fall inside the reservoir. Then remove the cap.
Now to install the generic cap, feed the chain around the bottom of the bottom of the master cylinder and come around to the opposite side of the cap. Install the J hook with the wind nut, tighten the chain and clip it onto the J hook, then tighten the wing nut. Ensure the cap is centered so we don’t risk the chance of any fluid leaking out. On the base of this cap, it uses a large rubber seal which works on a variety of reservoir fill openings.
Install the line onto the pressure bleeder tank, then clip on the quick disconnect to the reservoir cap. Ensure that valve at the quick disconnect is off so we can centralize a leak in any connections if there is one.
Pump up the system about 10 to 15 psi. I’m going to about 13psi, over 15 psi may risk the chance of damaging any seals in the system.
Monitor for any leaks.
Open the valve.
And then monitor the gauge for any leaks again. If a leak is present, you will see the gauge pressure drop slowly over time and tighten the connections as needed.
Once the system is pressurized, it will automatically replenish the system, but it’s always a good idea to keep an eye on the fluid level when done bleeding each wheel cylinder.
Starting with the furthest wheel from the master cylinder first, remove the rubber cap on the bleeder and then install a line wrench of the correct size, attach a clear rubber hose which fits tight around the bleeder, that goes directly to a drain pan or bottle.
Loosen the bleeder screw and watch for fluid entering the line. Typically I like to keep the line elevated, allowing it to fill with fluid so I can monitor when air bubbles are leaving the bleeder screw. Watch the leave until no more bubbles are leaving the bleeder screw, then tighten.
Moving onto the other wheel, driver’s side. Be sure to keep an eye on the pressure, do not allow the pressure bleeder to go below 10psi. Also do not allow the fluid to get low either.
Install the wrench, then the clear hose going to a drain bottle or pan.
Loosen the bleeder screw, again elevating the line to monitor the bubbles. As a close up, you can see bubbling in the line. We do not want air in the line as it highly compressible than compared to a fluid and will jeopardize braking performance.
Once no more bubbles are present in the fluid, tighten the bleeder screw.
Remove the pressure bleeder. This is done by pressing the pressure relief valve on the fill cap, ensure the gauge is at zero.
Turn off the valve.
Disconnect the line at the cap.
And now remove the cap. Do not keep the reservoir open for an extended period of time as brake fluid absorbs moisture which affects it’s performance. If you’re wondering how to test the quality of brake fluid, I do have a video on that so be sure to check it out.
If there is too much fluid in the reservoir, use a turkey baster to remove it. The fluid level should be between the minimum and maximum lines.
Step 8: How to Adjust the Drum Brakes
The last step is adjusting the brake pads as we did move the automatic adjusters. First press the brake pedal in order to center the shoes.
Remove the rubber cover in the backing plate for the automatic adjuster. Each side will rotate in different directions, using a standard screwdriver, rotate the star wheel on the automatic adjuster until there is mild drag on the drums.
In this example to give a better view, with the drum off, here is how the adjustment is done.
If they’re too tight, then use another screwdriver to push the lever away and rotate the star wheel in the opposite direction.
Step 9: Check Pedal Feel
Once done, reinstall the wheels. As a tip, you can also drive the vehicle in reverse, however it is safer to adjust the brakes by hand as the pedal movement maybe quite far depending on how far they’re out of adjustment.