in General

Brake Fluid Changes – Keep On The Black Stuff!

Brake Fluid. Is it really that important that we change it? Well that depends if you fancy wrapping your car round a tree really. It’s alarming the amount of vehicles we have in for service that have defective brake fluid as it’s not been changed in years, or in some cases never at all.

Brake fluid is hygroscopic oil which means that absorbs moisture during its life through the brake pipes or seals that it flows through. As the fluid absorbs more moisture the boiling point lowers which has a negative effect on braking.

A generic DOT 4 brake fluid will generally boil at 230°C but when it’s contaminated with moisture that boiling point can be as low as 155°C, which is alarmingly easy to achieve under normal breaking. Boiled brake fluid is turned to vapour which has absolutely no hydraulic properties whatsoever and you then have a high chance of finding yourself parked in the undergrowth – or worse.

Manufacturers recommend a fluid change every two years but in some cases, such as high performance cars, a brake fluid change is recommended every year.

The latest MoT regulations state that brake fluid should have no more than 4% moisture before failure. This has only recently become regulation but it’s alarming how many cars are still on the road with severely contaminated brake fluid.

Whilst we don’t include a brake fluid change on an interim and full service we will always advise if there is contamination and fluid changes start at £55 + VAT.

Don’t end up in a tree – click here to get a no obligation quote!

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Technical Manager at Service 4 Service
James is the main blogger for Service4Service. James is a full on car nut, ex racing driver, qualified racing instructor and has a habit of buying broken classic cars when down the pub...

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