The differences between DOT 3 and DOT 4 brake fluid

Every two years, it's usually time to change our car's brake fluid, so it's important to know the options available on the market . This way, we can ensure that the compound the mechanic intends to use is the correct one for our car.

Of course, depending on the age of our car or the daily functions it performs, it will be more appropriate to use DOT 3 or DOT 4. Furthermore, it is important to remember that we should never mix the two fluids , as this could impair the braking system's performance. This is something we cannot afford, since if the brake fluid does not maintain 100% of its qualities, it could cause mishaps on the road .

What characteristics does each type of liquid have?

First of all, both DOT 3 and DOT 4 are liquids composed of glycols, although the main difference is that the former is also made up of ethers and the latter of borate esters .

For this reason, DOT 3 has a dry boiling point of 205°C, while DOT 4 increases this figure to 230°C, meaning it allows the braking system to withstand higher temperatures .

Which fluid is more suitable, DOT3 or DOT4?

It will depend on the type of vehicle you have and what you use it for. If you have an older car or one that you simply use for short intercity trips, you may only need DOT 3 compound . To be sure, consult your vehicle's owner's manual or find out what the manufacturer says about the brake fluid you should use.

On the other hand, cars that include electronic systems, ABS, and other more advanced braking technology will likely require DOT 4. Although DOT 4 is somewhat more expensive, you shouldn't consider skimping on this expense because it could end up costing you and other road users less .