How to

How to check and test brake fluid

Share Resource:

Resource Highlights

Brake fluid is an essential part of the braking system. It acts as part of the hydraulic system which allows the brakes to function correctly. There’s a lot to remember about testing and checking brake fluid, so here’s a reminder. 

Brush up on brake fluid with this helpful video from the expert technicians at Delphi. We’ll go over some of the most important information ready for the next time you tackle these issues, including: 

  • Where to locate the brake fluid reservoir 
  • What the different DOT ratings mean 
  • When to check and when to change brake fluid.
Braking Maintenance Solutions How to Technicians 1 min read

What brake fluid do I need? 

You can find out which brake fluid the vehicle in question needs by looking at the cap on the brake fluid reservoir. There should be a DOT number written on there, which will tell you which specification you need. 

How often should brake fluid be changed? 

We recommend checking a vehicle’s brake fluid once a year, and changing it every two years to help your brakes stay in good shape. 

What does brake fluid do? 

Through hydraulic pipe, brake fluid converts the moment of the brake pedal, to the movement of the pad or shoe, on to the disc or drum. It also acts as a lubricant to keep the moving parts of the system working effectively. 

How do I check brake fluid level? 

Simply find the brake fluid reservoir in the engine bay. You can check the level of the brake fluid with a look at the clearly marked level indicators for Min and Max level. The ideal level is between these two markers. 

The fluid should also be checked for water content, as brake fluid will absorb water over time. 


Fill yp your details to hear more from our experts and get the latest updates from Delphi.

I have read and accept the <a href="">Terms of Use</a> and <a href="">Privacy Policy</a>

I agree to receive personalised marketing emails.

I would like to be kept up to date with promotions/marketing/features/events.

You can change your mind at any time by clicking the unsubscribe link in the footer of any newsletter email you receive from us, or by contacting us at <a href="[email protected]">[email protected]</a>

A mechanic holding a diagnostic tool


Discover our extensive range of OE-level diagnostic and test equipment for quicker, more accurate servicing and repairs.

Two mechanics ready to start training


Choose from our expert-led, accredited training courses to enhance your skills and prepare you for the vehicles of tomorrow.

where to buy

Find out where to buy Delphi parts

where to repair

Find your nearest Service & Diesel Centres

Select your Region