OEM 2005 Toyota 4Runner Brake Master Cylinder

2005 Toyota 4Runner Parts Questions & Experts Answers

• Q: How to overhaul the brake master cylinder on 2005 Toyota 4Runner?

  A: Work procedures for brake master cylinder overhaul require using lithium soap base glycol grease on mentioned parts while ensuring the ignition is off and performing 20 or more brake pedal depressions before starting. The first step includes draining brake fluid followed by quick spill cleanup while removing the front door scuff plate LH together with the front floor footrest and cowl side trim board LH and instrument panel finish plate and instrument panel finish panel sub-assembly lower. Start by disassembly of the 4 clips holding the steering column hole cover. Next, detach the clip which holds the push rod pin. Disconnect the 3 brake master cylinder connectors while tagging their proper reintegration positions before disconnecting the 4 brake lines using SST 09023-00101. Pull out the brake master cylinder by removing its 4 nuts before you can remove the brake booster gasket. A 5-mm hexagon wrench must be used to remove the bolt and disconnect the brake actuator bracket No.1 while extracting the brake fluid level warning switch connector. A pin punch together with a hammer should be used to remove the pin followed by screw and assembly removal steps while using a filler cap. Extract the 3 grommets inside the reservoir and the brake actuator hose by using needle nose pliers. Attachment of SST 09023-00101 enables the removal of brake actuator tube No.1 but the brake booster w/accumulator pump assembly requires mounting in a vise while maintaining pump cleanliness from foreign materials. Check how the brake booster pump assembly operates when connecting battery leads during the inspection process. Cut the brake booster accumulator assembly at points A and B and cover it with cloth before disposal to prevent gas discharge. Cut out the 6 bolts and gasket to access the solenoid of the master cylinder before using a wrench to remove the push rod clevis together with its rod operating adapter. Press the master cylinder piston inward to disassemble its boot and brake master cylinder kit until you expose the C-ring before pulling the piston straight. Use lithium soap base glycol grease on the new brake master cylinder piston before installing it with a new snap ring. The master cylinder boot along with the push rod clevis needs to be reinstalled and torque to 26 Nm (260 kgf-cm, 19 ft. lbs.) for each lock nut. First attach the master cylinder solenoid using a new gasket and six new bolts which need to be torqued to 32 Nm (326 kgf-cm, 24 ft. lbs.). Next install the brake booster accumulator assembly by applying 57 Nm (585 kgf-cm, 42 ft. lbs.) torque during the installation process with a new O-ring. Fasten the brake actuator bracket No.3 and brake booster pump bracket No.2 with correct torque values in place. Place the brake booster w/accumulator pump assembly and fasten it using a new clip while you reattach the wire harnesses. Position brake actuator tube No.1 by using SST 09023-00101 and torquing it to 14 Nm (143 kgf-cm, 10 ft. lbs.). Next, position the brake actuator hose followed by the reservoir grommets. Steal and tighten the brake master cylinder reservoir sub-assembly by screwing the reservoir screw at 1.7 Nm (17 kgf-cm, 15 inch lbs.) before installing the filler cap. First reattach the brake actuator bracket No.1 together with the brake booster gasket before installing the brake master cylinder that requires 4 nuts tightened to 14 Nm (145 kgf-cm, 10 ft. lbs.) and then reconnect the brake lines and connectors. After reinstalling all previous components you must bleed the brake booster w/accumulator pump assembly together with the brake line and master cylinder solenoid and verify the master cylinder operation together with brake pedal height, free play, reserve distance, fluid level and leakage.