The Ultimate Guide to Choosing Brake Fluid

Every car owner has encountered brake fluid losing its braking effectiveness and needing replacement. That's precisely why understanding when to replace it and which type to choose (DOT 3, DOT 4, or DOT 5.1) is more important than addressing the issue after it arise.

Why You Can’t Ignore Brake Fluid Replacement

Unlike engine oil, brake fluid isn't consumed by combustion—it absorbs moisture from the air. Over time, this lowers its boiling point, meaning your brake pedal could feel spongy or even fail during emergency stops. Most vehicles recommend replacing brake fluid every two years. Some brands, like Honda or BMW, specify even stricter replacement intervals in their manuals. While the importance of maintenance may not be immediately apparent, its criticality becomes starkly clear during sudden crise.

DOT 3, DOT 4, and DOT 5.1: What’s the Difference?

These are performance rating standards established by the U.S. Department of Transportation (DOT).
DOT 3 Brake Fluid—Suitable for older vehicles or those with low braking demands. Affordable and reliable, but not heat-resistant.
DOT 4 Brake Fluid — Features a higher boiling point, suitable for modern sedans, SUVs, and vehicles driven aggressively.
DOT 5 Brake Fluid (practically replaced by DOT 5.1) — Perfectly suited for sports cars, race cars, and performance enthusiasts. Though pricier, it maintains stable performance under extreme pressure.

How do I select the correct brake fluid for my vehicle?

For daily commuters, DOT 3 or DOT 4 is typically sufficient.
However, for vehicles from different regions, such as German brands (BMW, Mercedes-Benz, Audi, Volkswagen), DOT 4 is often the factory standard.
Japanese and Korean models (Honda, Toyota, Nissan) generally require DOT 4 for newer vehicles.
For performance car owners or those pursuing extreme driving, upgrading to DOT 5.1 is worth considering.
Overall, carefully review your owner's manual and select brake fluid according to the manufacturer's specifications, as they know your vehicle best.

When should it be replaced?

It's generally recommended to replace brake fluid every 2 years or approximately every 40,000 kilometer.
During routine maintenance, technicians will inspect your brake fluid using a testing pen to check for cloudiness and moisture content. If levels exceed acceptable limits, replacement is necessary.
We do not recommend self-inspection, as this directly impacts your safety. Professional testing and replacement ensure your driving safety.