Parts for your 2002 Daihatsu Gran move-Brake booster

2002 Daihatsu Gran Move brake booster: what it does and how to look after it

Referencing technical sources, the 2002 Daihatsu Gran Move is fitted with a vacuum brake booster (also called a brake servo). This is documented in the Daihatsu Gran Move/Pyzar G3-series Workshop Manual (Chassis – Brake, section BR), the Daihatsu Electronic Parts Catalogue for G303/G311 (which lists “Booster Assy, Brake” for petrol models through 2002), and multiple aftermarket catalogues that supply replacement vacuum boosters for the Gran Move/Pyzar range from 1996–2002. Those sources make it clear the booster is standard equipment on the 2002 model.

The brake booster on a 2002 Gran Move uses engine manifold vacuum to multiply pedal force, so the driver doesn’t need to stand on the pedal to stop quickly. It’s mounted on the firewall on the driver’s side, with the master cylinder bolted to its front. When it’s healthy, the pedal feels light yet progressive, and the car pulls up straight without drama.

There’s no fixed replacement interval for a booster, but at this age it pays to give it a once-over during regular servicing. A quick driveway test: with the engine off, pump the brake pedal until it’s firm, keep holding the pedal, then start the engine. If the booster and vacuum supply are good, the pedal should drop slightly as vacuum assist kicks in. No change, a constant hiss from the firewall, a rock-hard pedal, or the engine stumbling when the brake is pressed all point to leaks or a failing diaphragm or check valve.

During service, a tech will usually: inspect the vacuum hose for soft spots or cracking, confirm the one-way check valve holds vacuum, check the grommet at the booster, and look for brake fluid inside the booster (a sign the master cylinder is leaking past its rear seal). Any fluid contamination means the booster has to come out.

If replacement’s on the cards, it’s straightforward but fiddly: the master cylinder is removed, the pushrod free play is set to spec, the firewall nuts are torqued correctly, and fresh vacuum hose and check valve are fitted. The system is then bled with the correct brake fluid type as marked on the reservoir cap (usually DOT 3 or DOT 4). Given the Gran Move’s age, doing the hose and valve at the same time is cheap insurance. If the pedal ever goes rock-hard or stopping distances blow out, don’t drive on—organise a tow and get it sorted.

Popular questions about 2002 Daihatsu Gran Move brake boosters

Does the 2002 Gran Move have a brake booster?
Yes. The 2002 Gran Move (G303/G311 series) comes with a vacuum-assisted brake booster, also called a brake servo. It’s bolted to the firewall and uses engine vacuum to reduce pedal effort.

What are the common signs of a failing brake booster?
Hard brake pedal, a hissing noise from the firewall, longer stopping distances, the pedal not dropping slightly when the engine starts, or the engine stumbling when the brake is pressed. Any of these warrant a proper inspection.

Can the booster be repaired, or should it be replaced?
Quality remanufactured or new exchange boosters are commonly used. Reconditioning is possible but often slower and not always cost-effective. Always replace the vacuum hose and check valve when the booster is changed.