DOT 3: the reliable standard
DOT 3 brake fluid is one of the most common and widely used types. It is a glycol-based fluid and has a higher boiling point than water, which makes it less prone to vapour bubble formation in the brake system. However, its boiling point may decrease over time due to moisture absorption, which may adversely affect its performance in extreme conditions.
DOT 4 - balancing performance and cost
DOT 4 brake fluid is similar to DOT 3 in terms of composition, but has a higher boiling point and is more resistant to moisture absorption. This makes it a popular choice for vehicles requiring improved performance in high temperature conditions. DOT 4 offers a balance between performance and cost, making it an attractive option for many drivers.
DOT 5 - the silicone-based alternative
DOT 5 brake fluid differs from previous types in that it is silicone-based rather than glycol-based. This gives it non-hygroscopic properties, which means that it does not absorb moisture. While this may seem to be an advantage, DOT 5 also has a higher boiling point and may be less efficient in extreme temperature conditions. In addition, it is not compatible with systems designed for glycol-based brake fluids.
DOT 5.1: improving the formula
DOT 5.1 brake fluid is an evolution of DOT 4. Although it is glycol-based, it has an even higher boiling point and improved performance in extreme conditions. It is less susceptible to moisture absorption than DOT 3 and DOT 4, which means it retains its performance properties for longer.