Car owners in Spain regularly face the need to replace their brake fluid. This procedure is usually performed every two years to ensure the reliable operation of the braking system and maintain safety on the roads.
There are different types of brake fluids on the market, with DOT 3 and DOT 4 being the most popular. The choice between them depends on the age of the vehicle, its technical specifications, and operating conditions.
DOT 3 and DOT 4 have a similar base — both are produced using glycols. However, their chemical compositions differ: DOT 3 contains ethers, while DOT 4 contains borate esters. This affects the fluid’s temperature properties. DOT 3 has a dry boiling point of about 205°C, whereas DOT 4’s is higher, around 230°C. As a result, DOT 4 performs better under high loads and is suitable for modern cars with advanced braking systems.
For older car models, or those mainly used for short trips on city and suburban roads, DOT 3 is often sufficient. Drivers are advised to consult their vehicle’s manual or the manufacturer’s recommendations to select the appropriate type of brake fluid.
Modern cars equipped with electronic stability systems and reinforced brakes generally require the use of DOT 4. This fluid is more expensive but offers greater reliability during intensive operation and high temperatures, which is especially important for the hot climate in some regions of Spain.
It is important to remember that mixing DOT 3 and DOT 4 is not recommended. Doing so can reduce braking efficiency and pose a road safety risk. When replacing fluid, it is necessary to completely remove the old mixture and fill in new fluid that meets the vehicle’s specifications.
Experts advise not to skimp on brake fluid quality. Timely replacement and the correct choice of fluid help prevent accidents and extend the service life of brake components.
Thus, the choice between DOT 3 and DOT 4 depends on the type of car, its age, and operating conditions. For newer models and intensive driving, DOT 4 is preferred; for older and less stressed vehicles, DOT 3 is sufficient. In any case, road safety in Spain should remain a priority for every driver.
