Brake fluid

High-quality brake fluid for safe braking under all conditions

The few times you look under the hood of your car are probably to check oil or fill the windscreen washer reservoir. Much more isn't necessary either, because our mechanics take care of all those other checks during a service. Such as the level and quality of brake fluid – a small component with big impact on your safety.

Why is brake fluid important?

Brake fluid is the invisible link between your brake pedal and your brakes. When you brake, the master cylinder builds hydraulic pressure in the brake fluid. This pressure is sent via brake lines to the wheel cylinders or brake calipers, which then press the brake pads against the brake discs. Without good brake fluid, your brakes don't work.

But brake fluid isn't just any fluid. It must be able to handle extreme pressure, high temperatures and must continue to function reliably for years. That's why the quality of your brake fluid is crucial for your safety.

Brake fluid absorbs water

Is checking brake fluid really necessary? Yes, absolutely. Brake fluid is hygroscopic – that means it absorbs moisture from the air. This happens slowly but surely, even in a closed braking system.

What are the consequences?

When brake fluid absorbs water, various problems arise:

• Lower boiling point – water boils at 100°C, while good brake fluid has a boiling point of 230°C or higher. With water in the fluid, this boiling point drops quickly.
• Rust formation – water causes corrosion in the brake circuit, on brake cylinders, brake lines and brake calipers.
• Vapor lock – during prolonged or heavy braking (for example during a descent in the mountains), the fluid can start to boil. Vapor bubbles then form in the braking system, causing the brake pedal to feel spongy or even to be pressed to the bottom. Your brakes then hardly work anymore.

These are dangerous situations you can easily prevent by periodically refreshing the brake fluid.

When should brake fluid be replaced?

Most car manufacturers recommend refreshing brake fluid every 2 to 3 years, regardless of mileage. This is stated in your car's instruction manual or service passport.

Why so often? Because brake fluid gradually absorbs moisture, even if you use the car little. After 2 to 3 years, the fluid contains enough moisture to cause problems.

At Autobest, we check the level and quality of your brake fluid at every major service. If necessary, we refresh the fluid, so you can always continue braking safely.

Modern braking systems place higher demands

Modern cars are equipped with braking systems that place increasingly higher demands on brake fluid. More and more braking force is generated, and modern safety systems such as ABS and ESP work extremely fast.

What does this mean for brake fluid?

ABS and ESP pump brake fluid through the braking system several times per second to regulate brake pressure. This requires a fluid that:

• Can flow quickly, even at low temperatures
• Doesn't overheat with intensive use
• Has a high and stable boiling point
• Lubricates well to prevent wear
• Prevents rust formation

Ordinary, cheap brake fluid often doesn't meet these requirements. That's why it's important to use high-quality brake fluid specifically developed for modern braking systems.

Bosch ENV4 and ENV6: high-quality brake fluid

Bosch is the inventor and developer of ABS and ESP, and also developed its own brake fluid that meets the very highest quality requirements: the Bosch ENV4 and ENV6.

These brake fluids were specially developed for today's modern, demanding braking systems. They distinguish themselves through:

Excellent flow properties at low temperatures
Even in winter, the fluid continues to flow smoothly, so your brakes respond immediately well.

High boiling point
Bosch ENV4 has a dry boiling point of at least 230°C and a wet boiling point of at least 155°C. ENV6 goes even further with a dry boiling point of at least 260°C. This allows you to continue braking safely even under extreme conditions.

Excellent lubricating properties
The fluid lubricates the moving parts in the braking system, reducing wear and extending lifespan.

Rust-resistant
Protects the braking system against corrosion, even if small amounts of moisture enter the fluid.

Compatible with modern safety systems
Specially formulated for use with ABS, ESP, ASR and other electronic braking systems.

ENV4 or ENV6: which do you need?

The choice between ENV4 and ENV6 depends on the specifications prescribed by the car manufacturer. Modern cars with heavier braking systems or intensive use (for example sports cars) often require ENV6 because of the higher boiling point.

Our workshop receptionist and mechanics are happy to advise you which brake fluid is most suitable for your car. We look at:

• The car manufacturer's specifications
• The type of braking system in your car
• Your driving behavior and use of the car

This way you know for sure you get the right fluid for maximum safety.

Why choose Bosch brake fluid?

You can also buy cheaper brake fluid, but is that wise? Bosch brake fluid offers you:

• Proven quality – developed by the inventor of ABS and ESP
• Meets highest standards – DOT 4 and DOT 5.1 specifications
• Extra safety – high boiling point prevents vapor lock
• Longer lifespan – protects against corrosion and wear
• Optimal performance – especially for modern braking systems

With brakes you don't want to compromise. Bosch brake fluid gives you the certainty that you can always brake safely, under all conditions.

How do we replace brake fluid?

Refreshing brake fluid is specialist work. Our mechanics:

1. First check the level and quality of the old fluid
2. Drain the old fluid at each wheel
3. Fill the system with new Bosch brake fluid
4. Thoroughly bleed the braking system to remove all air bubbles
5. Check the operation of the brakes
6. Test the brakes on the road

It's important this is done professionally. Air in the braking system can lead to a spongy brake pedal and reduced braking force.

Signs that you need to refresh your brake fluid

Usually you don't immediately notice that your brake fluid needs replacement. That's why periodic replacement is so important. Yet there are some signs:

• The brake pedal feels softer or spongier than normal
• The brake fluid in the reservoir looks dark or cloudy (should be clear)
• The brakes respond slower than usual
• It's been longer than 3 years since the fluid was replaced

Recognize these signs? Stop by for a check.

Have brake fluid checked or refreshed?

Not sure when your brake fluid was last replaced? Or do you have the feeling your brakes aren't responding optimally? Stop by for a free check. We check the level and quality of your brake fluid and advise you whether replacement is necessary.

Schedule an appointment via our website or call us at 0499 - 390 475. Good brake fluid is a small investment with big impact on your safety.