Brake fluid is an essential component of any car’s braking system. It is responsible for transmitting the force of the brake pedal to the brake pads or shoes, which in turn apply pressure to the rotors or drums and bring the vehicle to a stop. But not all brake fluids are created equal, and choosing the right one for your car can be crucial for its performance, safety, and longevity. In this article, we will discuss the different types of brake fluids, their properties, and how to select the best one for your car.
The Basics of Brake Fluid
Brake fluid is a type of hydraulic fluid that is designed to withstand high temperatures and pressures while maintaining a consistent viscosity and lubrication. It is usually made of glycol-ether or silicone-based compounds, which have different boiling points, viscosity, and compatibility with different materials.
Brake fluids are classified according to their boiling points, which determine their ability to resist vaporization, a phenomenon that can occur when the fluid is exposed to high temperatures or moisture. The boiling point of a brake fluid is divided into two categories: dry boiling point and wet boiling point.
The dry boiling point refers to the temperature at which the brake fluid boils without any water contamination, while the wet boiling point indicates the boiling point of the fluid after it has absorbed a certain amount of moisture, which can lower its boiling point and compromise its performance.
Types of Brake Fluids
There are four main types of brake fluids on the market: DOT 3, DOT 4, DOT 5, and DOT 5.1. These are regulated by the Department of Transportation (DOT) and have different properties and applications.
DOT 3 is the most common type of brake fluid used in most vehicles. It has a dry boiling point of at least 401 degrees Fahrenheit and a wet boiling point of 284 degrees Fahrenheit. It is compatible with most rubber and metal components and is affordable and widely available. However, it can absorb moisture over time, which can lower its boiling point and affect its performance.
DOT 4 is a higher-specification brake fluid that has a dry boiling point of at least 446 degrees Fahrenheit and a wet boiling point of 311 degrees Fahrenheit. It is compatible with most DOT 3 systems but has better performance under high-temperature conditions and is less prone to moisture absorption. It is recommended for vehicles with ABS systems, high-performance vehicles, and those that operate in extreme conditions.
DOT 5 is a silicone-based brake fluid that has a dry boiling point of at least 500 degrees Fahrenheit and a wet boiling point of 356 degrees Fahrenheit. It is not compatible with most DOT 3 or DOT 4 systems and is typically used in military vehicles, hot rods, and show cars. It is not hygroscopic, meaning it does not absorb moisture, but it is more expensive and harder to find than other types of brake fluids.
DOT 5.1 is a high-performance brake fluid that has a dry boiling point of at least 500 degrees Fahrenheit and a wet boiling point of 356 degrees Fahrenheit. It is compatible with most DOT 3 and DOT 4 systems and has better performance under high-temperature conditions and lower viscosity at low temperatures. It is recommended for vehicles with ABS systems, high-performance vehicles, and those that operate in extreme conditions.
How to Choose the Right Brake Fluid
Choosing the right brake fluid for your car depends on several factors, such as the make and model of your vehicle, the type of braking system, the climate and driving conditions, and your personal preferences and budget.
If your vehicle’s owner’s manual specifies a particular type of brake fluid, you should follow its recommendations to ensure proper performance and avoid voiding your warranty. Most newer cars are designed to use DOT 3 or DOT 4 brake fluid, but some high-performance vehicles may require DOT 5 or DOT 5.1 brake fluid.
If you are upgrading your braking system, such as installing larger brakes or a high-performance brake kit, you may need to use a higher-specification brake fluid to match the increased demands. In general, a higher boiling point brake fluid is better suited for aggressive driving, racing, towing, or other high-stress situations.
Brake Maintenance at EAD Motorsport
Car enthusiasts in Thousand Oaks, Agoura Hills, and all of the 
surrounding locales have a trusted choice for brake system maintenance – EAD Motorsport. Our mechanics are highly trained and understand everything there is to know about keeping cars running their best. Rather than go with unpredictable or subpar services, take your vehicle to EAD Motorsport for top-of-the-line care that’s tailored to each customer’s unique needs. Prevent costly accidents from malfunctioning systems by trusting our professionals today! With EAD Motorsport, your car will always be in tip-top shape and you can enjoy the drive without worry.