Installing the LandCruiser Bendix Ultimate 4WD Brake Booster Upgrade

If you own a 70 or 80 Series LandCruiser, upgrading your Brake Booster is one of many ways to increase braking performance. By multiplying the vacuum assistance given to the braking system, stopping power is increased along with reduced pedal effort. Bendix offers the Ultimate 4WD Brake Booster upgrade and in this video, we’re going to give you a brief overview of how to install the upgrade. As always, this upgrade should only be performed by a qualified automotive technician.

First, you’ll need to evacuate vacuum pressure from the booster by removing the main vacuum line going to the booster, taking note of any check valves present.

Next, remove the lines going to the brake master cylinder and any electrical connectors associated with the master cylinder.

If possible, try to minimise any fluid loss from the master by plugging the ports on the master and placing blockers on the brake lines as this will aid in bleeding the system on assembly. From there, undo the two master cylinder bolts and remove the cylinder from the booster.

Then, inspect the plunger seal and replace the master cylinder if there are any signs of leakage present. When storing the master cylinder dry during the booster install, you will need to bench bleed the master cylinder.

Once the hydraulic system has been opened, ensure that the ignition is not turned on until after the master cylinder and ABS unit brake pipes have been bled. When the ignition is turned on, the ABS unit will cycle and draw air into the system, which will require the use of a scan tool to activate the ABS bleeding process.

To remove the brake booster, get underneath the dash, remove the retaining clip from the clevis pin, and slide the clevis pin out of the clevis to disconnect the booster pushrod from the brake pedal.

Next, undo the 4 nuts that hold the booster to the firewall.

The booster can then be removed, taking note of the spacer and gasket fitted between the booster and firewall. Be sure to note the orientation and transfer these parts onto the Upgraded booster.

Next, measure the old booster rod length with the clevis fork. Then, remove the fork and fit it to the new Bendix booster, adjust it until it is the same length as the old booster and lock it off with the nut.

From there, check the old booster pushrod length using Vernier calipers and a thick steel ruler. First, measure the thickness of the ruler and take note as you will need to minus this from the depth measurement. Then, place the Vernier on the ruler in the booster and measure the depth.

Subtract the ruler thickness from the booster pushrod depth and this will give you the final measurement. 23mm is the correct Toyota specification and a variation tolerance of 0.25mm is acceptable on either side of the target measurement. If your measurement is within spec, you won’t need to adjust the pushrod unless preload is identified in the next step.

From there, check the new Bendix brake booster’s pushrod depth using the same method to ensure the correct 23mm pushrod length. Once you’ve confirmed this, you will then need to verify with the master cylinder. To do this, remove the o-ring and slide the master cylinder into the booster to test for clearance between the pushrod end and the master cylinder.

The pushrod end must not preload or contact the master cylinder. The ideal distance between the pushrod and the master cylinder is 0.5mm. To achieve the correct distance, undo the lock nut and adjust until you’ve reached the correct measurement.

Next, ensure that the lock nut is refitted and tightened, and the o-ring is refitted to the master cylinder before final assembly.

Now, the Bendix Ultimate 4WD Brake Booster can be installed into the vehicle with the spacer fitted. With the new booster in position, go under the dash and refit the firewall nuts to the booster. Then, connect the pushrod to the brake pedal via the clevis pin.

Next, refit the vacuum line and master cylinder, ensuring that the pushrod end is mated squarely to the master cylinder. Then, refit the brake pipes, adjusting into the new position as required.

From there, make sure the ignition is off and bleed the two brake pipes from the master cylinder at the ABS unit side fittings. This requires a second person to depress the brake pedal so that air can be expelled from the two lines going into the ABS unit.

Tighten the lines before the pedal is released so that no air is drawn into the lines from the fittings. Repeat this several times until there’s no air in the lines.

Once you have a firm brake pedal, the system can be tested with the ignition on. If acceptable, move on to testing with the engine running. If air enters the ABS hydraulic system, the use of a compatible scan tool for ABS applications is required.

If you fail to activate the ABS pump whilst bleeding air out of the ABS system will result in air trapped within the system, meaning a soft brake pedal and excessive pedal travel. Further fine-tuning of the booster pushrod length may also be required to achieve the correct pedal height and the brake light switch operation.

Once complete, the brake pedal pressure should feel different to the old factory booster. This will be most notable at idle with a slight drooping of the pedal. This is normal and does not affect braking performance.

To troubleshoot any potential issues, refer to the chart below.

For more Brake technical information or to see the range of 4WD upgrade brake boosters from Bendix visit our website at the link below.

For more information on Bendix Ultimate 4WD products, click HERE.

To find your nearest Bendix stockist, click HERE.

For the latest Bendix news and updates, visit our Facebook page.