Can you mix brake fluid types? I have been told that I must always use DOT 3 and I know DOT 4 has a higher boiling point.
The rule of thumb I follow is, DOT 4 will go in any car that calls for DOT 3. Just don’t go the other way!
Always use a fresh unopened bottle of brake fluid. Never ever use a bottle that has been opened sitting on the self. Even if the lid is on tight, moisture can still get in the bottle!
Brake fluid is Hygroscopic this means it absorbs moisture like a sponge! Moisture in your brake system can cause serious problems such as a soft, spongy brake pedal to rust build-up, which will make brake parts stick or bind up!
Return to frequently asked questions