The brake system is just one of these points which are an extremely important to take care of since you really desire it to role properly in one emergency situation.

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The brake fluid is one of these points that you need to replace every one or 2 years otherwise, that may reason rust within the brake system and also damage other parts.

There are two general types of brake fluids space produced: silicone or glycol basis. Dot3 and also Dot4 are renowned glycol-based brake liquid options easily accessible for many vehicles. If Dot3 is famous with normal drivers, Dot4 is much more common in newer car models.

But what is the difference in between them and also can you mix them v each other?

Contents show
dot 3 vs. Dot 4 Brake liquid Differences
have the right to you mix period 3 and also Dot 4 Brake Fluid?
can you mix period 5 through dot 3 and also dot 4?
What does the boiling suggest mean?
Dot3 vs. Dot4: i m sorry one is the better brake fluid?

Dot 3 vs. Period 4 Brake liquid Differences

The main differences in between the period 3 and Dot 4 brake liquid are the boiling point. The dot 4 brake fluid does have actually both a greater wet and also dry boiling point and is better suited for higher performance.

Both dot 3 and Dot 4 brake fluids space glycol-based assets used in your braking system. They are hygroscopic and also absorb water indigenous the atmosphere, which way that treatment must it is in taken once storing and also regularly replacing perhaps contaminated fluids.

TypeWet boil PointDry cook PointComposition
DOT 3400°F/205°C285°F/140°CGlycol Ether
DOT 4445°F/230°C310°F/155°CGlycol Ether/Borate Ester
DOT 5500°F/260°C355°F/180°CSilicone
DOT 5.1500°F/260°C355°F/180°CGlycol Ether/Borate Ester

Can friend mix dot 3 and also Dot 4 Brake Fluid?

Yes, period 3 and also Dot 4 brake fluid can it is in mixed. It’s because both these are glycol-based brake fluids, which method that they are compatible through each other. If your auto has dot 4 native the factory, it’s not recommended to to fill it through Dot 3, though; but the other means is fine.

If you have actually Dot 3 in your auto from the factory and you recognize that girlfriend are often driving v a trailer or in steep hills, we strongly recommend refilling it through Dot 4 instead.

Can friend mix period 5 v dot 3 and dot 4?

Dot5 is a silicone-based brake fluid. That does not absorb water indigenous the air and is no compatible with ABS systems. The maintains that is integrity and works well. It likewise has a greater boiling point than the brake fluids Dot3 and Dot4, make it more compatible through excessively wild driving.

However, the is not compatible through Dot3 or Dot4 liquids and should never ever be combined with them. Girlfriend must also follow your manufacturer’s references to know whether your braking mechanism is compatible through Dot5 brake fluid.

What does the boiling suggest mean?


As us told before, dot 3 and Dot 4 brake fluids are hygroscopic, which way that lock absorb water over time. This is the factor why you should replace it yearly or second year.

When you journey your automobile hard in ~ hills or v a trailer and braking a lot, the brake liquid will heat up fast. If the is heater up also much and starts to boil – you will shed the ability to brake her car, which is the the very least you want to occur at a hill with a trailer. Because of this it is vital to have such a high boiling suggest as possible.

The wet boiling suggest is measured as soon as the brake fluid contains water, and also the dried boiling suggest is without water.

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Dot3 vs. Dot4: i beg your pardon one is the better brake fluid?

Dot3 is the much more popular the the 2 brake fluids, but Dot4 is quickly gaining popularity because it is compatible through the standard traction control and also anti-lock braking system.

Dot 4 has higher boiling points, do it far better for all types of applications; also though that is often a little bit much more expensive, that is worth obtaining it instead.