Is DOT 3 and dot 4 brake fluid?
As a car owner, understanding the different types of brake fluid is crucial for maintaining your vehicle's safety and performance. In this article, we will explore the differences between DOT 3 and DOT 4 brake fluids, their applications, and why choosing the right one matters for your vehicle.
What Are DOT 3 and DOT 4 Brake Fluids?
DOT 3 and DOT 4 brake fluids are both glycol-based fluids used in hydraulic brake systems. They are designed to transfer force from the brake pedal to the brake components, ensuring effective stopping power. However, there are key differences between the two that can affect their performance and suitability for different vehicles.
Key Differences Between DOT 3 and DOT 4
- Boiling Point: DOT 3 brake fluid has a lower boiling point (approximately 205°C or 401°F) compared to DOT 4, which has a higher boiling point (around 230°C or 446°F). This means DOT 4 is better suited for high-performance vehicles or those that experience more intense braking conditions.
- Water Absorption: Both fluids absorb moisture over time, but DOT 4 has a lower rate of water absorption, which helps maintain its performance longer. This is particularly important in preventing brake fade during heavy use.
- Compatibility: DOT 3 and DOT 4 fluids are generally compatible with each other, but it is always best to use the fluid specified by your vehicle manufacturer. Mixing different types can lead to reduced performance and potential damage to the braking system.
When to Use DOT 3 or DOT 4
Choosing between DOT 3 and DOT 4 brake fluid depends on your vehicle's requirements and your driving habits:
- DOT 3: Ideal for standard vehicles and everyday driving conditions. It is often used in older cars and those that do not require high-performance braking.
- DOT 4: Recommended for newer vehicles, performance cars, and those that undergo frequent heavy braking. If you drive in mountainous areas or tow heavy loads, DOT 4 is the better choice.
Conclusion
Understanding the differences between DOT 3 and DOT 4 brake fluids is essential for maintaining your vehicle's braking system. Always refer to your owner's manual for the manufacturer's recommendations and ensure you use the appropriate fluid for your driving conditions. Regular maintenance and timely fluid changes can significantly enhance your vehicle's safety and performance on the road.
Frequently Asked Questions
Are DOT 3 and DOT 4 compatible?
Yes. DOT 3 brake fluid is compatible with DOT 4 brake fluid. However, DOT 4 offers a higher boiling point. DOT 5.1 is used in high-performance and heavy-duty applications due to its high boiling point.
What vehicles use DOT 4 brake fluid?
DOT 4 is used in some euro and domestic vehicles. DOT 4 Plus is used in Mercedes and Volvo. DOT 4 Low Viscosity is used in some BMW models. Finally, DOT 4 Racing usually has an added blue color.
How do I know if I need DOT 3 or DOT 4 brake fluid?
DOT 4 brake fluid has higher wet/dry boiling points than DOT 3, making it a better choice for higher temperature braking applications, like in high-performance vehicles.
What happens if you mix DOT 3 and DOT 4 brake fluid?
Dot 3 and Dot 4 brake fluid are compatible with each other if you want to mix them. There will be no negative impacts from mixing the two and the brakes will still function as normal.
Can I use Super DOT 4 instead of DOT 3?
SUPER DOT 4 BRAKE FLUID is suitable for use where the vehicle manufacturer specifies DOT 3 or DOT 4 brake fluid.
How to do a brake flush?
Flushing Brake Fluid
- On a level surface, set the car in gear and place a stop behind the tires to keep it from rolling.
- Open the hood and locate the master cylinder.
- Using a turkey baster, suck out all the fluid.
- Refill the reservoir back up to the fill line using fresh brake fluid.
What does DOT 3 brake fluid look like?
DOT 3 Brake fluid: Typically in clear, yellow, blue, and red shades. DOT 4 Brake fluid: Typically in light yellow or crimson red shades. DOT 5 Brake fluid: Typically in purple shades. DOT 5.1 Brake fluid: Typically in clear, yellow, and blue shades.
Can I use DOT 4 brake fluid in older cars?
Choosing the Best Brake Fluid for Your Classic Car
We recommend DOT 3 or DOT 4 because these brake fluids are glycol-based and hygroscopic. They are the kindest on your braking system.
Is it OK to mix old and new brake fluid?
Or, is mix of different grade fluid ? Basically, not recommended.
Does DOT 4 brake fluid have a higher boiling point than DOT 3?
DOT 3 and DOT 4 brake fluid formulas actually have different recommended service increments. DOT 3 brake fluid typically has lower boiling point temperatures, thus moisture is absorbed into the brake fluid more quickly than DOT 4.
