Parts for your 2005 Toyota Highlander-Brake booster

2005 Toyota Highlander (Kluger) Brake Booster — What It Does and How to Look After It

Yes, a brake booster is fitted to the 2005 Toyota Highlander (sold as Kluger in Australia and New Zealand). Technical references including the Toyota Highlander/Kluger Factory Service Manual (Brake section: vacuum brake booster testing and removal/installation) and Toyota’s Electronic Parts Catalogue list a “Booster Assy, Brake” for 2005 non-hybrid models. General repair guides (e.g., Haynes/Chilton covering 2001–2007) also detail the vacuum-assisted booster on this platform.

The brake booster’s job is to use engine vacuum to amplify the driver’s pedal effort, so stopping feels light and confident rather than heavy. It sits between the brake pedal and master cylinder, with a one-way check valve and a vacuum hose running to the intake manifold. When it’s healthy, pedal feel is consistent and braking requires minimal effort, when it’s not, the pedal can go rock-hard, the engine may idle roughly when braking, or stops might feel longer than they should.

As part of regular servicing, it’s worth giving the booster and its plumbing a quick once-over. Look for perished or loose vacuum hoses, a cracked grommet at the booster port, or signs of brake fluid leakage from the master cylinder into the booster (which can ruin the diaphragm). A standard driveway test is simple: with the engine off, pump the pedal a few times to deplete reserve vacuum, hold pressure on the pedal, then start the engine—if the booster is working, the pedal should drop slightly.

• Keep the vacuum hose, clamps, and check valve in good nick, replace if brittle or leaking.
• If the master cylinder is damp or weeping, sort that promptly to protect the booster.
• Flush brake fluid (Toyota-spec DOT 3) about every 2 years to maintain a crisp pedal and protect seals.
• After any booster replacement, adjust pedal free play and the booster push-rod to spec, and bleed the brakes properly.

Replacing the booster isn’t hard for a competent DIYer, but clearance at the firewall and under the dash can be fiddly. Expect to remove the master cylinder from the booster (lines off and re-bleed), disconnect the pedal clevis, and undo the booster’s mounting nuts. Use quality parts, new gaskets where required, and a torque wrench rather than guesswork. Note: the 2006–2007 Highlander Hybrid uses a different electro-hydraulic system with specialised bleeding—different kettle of fish to the 2005 non-hybrid vacuum booster.

How do you test the brake booster on a 2005 Highlander/Kluger?

With the engine off, pump the brake pedal several times to exhaust any stored vacuum. Press and hold the pedal, then start the engine. A healthy booster will let the pedal sink slightly as vacuum assist comes on. Also check the vacuum hose and one-way check valve for leaks by listening for hissing and inspecting for cracks or loose fittings.

What brake fluid should be used after booster or master cylinder work?

Use Toyota-spec DOT 3 brake fluid. When the hydraulic system is opened, bleed thoroughly to clear air. It’s good practice to flush the fluid about every two years to keep corrosion at bay and maintain a consistent pedal.

Is the Hybrid model’s brake booster the same as the non-hybrid?

No. The 2006–2007 Highlander/Kluger Hybrid uses an electro-hydraulic brake actuator and different assist strategy. The 2005 non-hybrid uses a conventional vacuum booster. Procedures and parts are not interchangeable, and Hybrid bleeding typically requires scan-tool control of the pump/valves.