Brake fluid change – all you need to know

Brakes and the surrounding components are integral to keeping a vehicle road legal and suitable for travelling across the country.

This guide looks at everything you will need to know about brake fluid and changing it when necessary.

Brake fluid is a type of hydraulic liquid that is used in brake and clutch systems in many types of vehicles.

It is an important part of the braking process. When a driver applies force to the brakes, the fluid amplifies the force to slow the vehicle – as well as acting as a lubricant in the system that also prevents corrosion to other crucial components.

Brake fluids are normally glycol-ether or silicone-based and are designed to have a high boiling point. This is because the braking process can create intense heat quickly – especially during an period of prolonged braking, such as driving down a steep hill. 

Topping up and replacing the fluid are important parts of basic vehicle maintenance. 

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Also known as a brake fluid flush, or brake fluid replacement, a brake fluid change is the process of removing the old liquid and adding some fresh, clean solution.

It is an important part of regular car maintenance, and something that can either be done by a mobile mechanic or at a local trusted garage.

Over time, brake fluid absorbs moisture from the air, which leads to its decreased effectiveness in the braking process and helping fight corrosion.

The car owner’s manual will outline the type of brake fluid your vehicle will need and how often it should be replaced.

Changing brake fluid is a delicate process and something that should only be carried out by a Mobile Mechanic or at a local garage. 

Here are the steps taken by a mechanic to replace the brake fluid:

• Open the bonnet and locate the fluid reservoir
• Using a siphon or transfer pump to remove the old fluid
• Refill the reservoir to the suggested limit with the correct formula

A brake fluid change at a mechanics in the UK will cost from around £80 – although this can be significantly more large or premium vehicles. 

A higher quality brake fluid and replacing the old solution will come with a higher price tag of over £100.

Drivers should also be aware that if the fluid hasn’t been changed in a while, then there could also be damage to other parts of the braking system – and this can come with a much higher cost.

Car owners should change their vehicle’s brake fluid every two years, or every 24,000 miles (whichever comes first).

However, this can vary depending on the make and model of the vehicle, quality of the brake fluid, and driving style. 

In some cases, owners will need to have the brake fluid changed every year during their MOT or service. Book your MOT and Service Plan today.

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