First, we are going to learn what is the DOT abbreviation and what it means. Then we will go through all of the different types of DOT fluids and then focus primarily on the DOT 5 brake fluid where we will list all the positives and negatives of running this fluid and why you should or should not run this brake fluid on your car. Then we will learn how to convert your brake fluid from DOT 3 To DOT 5 fluid on your car. So, if you want to learn more, please follow along. What Is DOT Brake Fluid? Note: Do not mix with DOT 5 brake fluid but can be mixed safely with other DOT 3 and DOT 4 fluids. Features & Benefits: Having said that, few motorcycles use or have used DOT 5 in the past. But with the ABS not working well with DOT 5, almost all vehicles use DOT 4 nowadays. DOT5 brake fluid is especially good at maintaining efficacy during very high temperatures and is completely immune to water in the brake lines. This makes it an attractive choice for any driver. However, if your car is not designed to handle silicone-based brake fluids then it can cause more harm than it fixes if you add it to your system. The Mobil Brake Fluid DOT 5.1 500ml is a high-performance brake fluid. This is suitable for all disc, drum and anti-skid braking systems used in average to high-performance vehicles requiring DOT 3 or DOT 4 level performance. It is based on polyethylene glycol ether technology to provide the highest level of brake and clutch performance in modern as well as older model automotive and commercial vehicles. This is a synthetic fluid for hydraulic braking systems.

There are also some disadvantages to using DOT 5 brake fluid. When heated, it expands greatly, and the additives can evaporate, resulting in a more spongy texture. The first and biggest con when it comes to this fluid is that it cannot run on any type of brake system. It means that this fluid can only be used on brake systems that have DOT 5 brake fluid compatibility.Since DOT 4 and 5.1 are both glycol-based brake fluids they are compatible with each other, which means they can be readily mixed without harming your brake system. It is important never to mistake DOT 5.1 (glycol-based) with DOT 5 which is silicone-based and should never be mixed with any other DOT fluid. A DOT 5 brake fluid does not absorb moisture and does not affect painted surfaces, making it ideal for high-performance vehicles. Using this brake fluid protects the braking system from the effects of bad weather. For example if you introduced DOT 3 into a brake previously filled with DOT 5.1 then you will probably be left with a brake fluid with a lower boiling point. I say 'probably' as it depends on the service life of the older fluid but you get the idea - not a great deal can go wrong mixing glycol-based DOT fluids. Polyethylene glycol ether is the basis for the braking fluid’s high-performance properties. Source:Oards Automotive Hub

This way you will get the best performance from the fluid when it comes to the dry boiling point temperature which will be 446 degrees when it comes to installing a new fluid, while if you mix it, you will only get a wet boiling point performance of 311 degrees which is not that good after all.

Mineral Oil Boiling Temperatures

Dot 4 is a more commonly used type of brake fluid as compared to DOT 5. It also comes with a cheaper price tag and is used as a standard option in many average domestic cars. Then we learned more about the pros and cons of the DOT 5 and how it outperforms other fluids as well as the comparison with the DOT 3. F.A.Q

DOT 5 brake fluid (not to be confused with DOT 5.1) is fundamentally different than the rest of the DOT fluid range in that it is silicone based brake fluid. As we said, you cannot mix DOT 5 brake fluid with any other kinds of brake fluid. Because of the compressibility of silicone-based brake fluids you don't want to use them with ABS brakes anyway because they will not function as well. More precisely to use the good old glycol borate ester formula from the previous generations but to make it better and perform as the DOT 5 brake fluid.

Which brands use DOT fluid?

We at EBS had believed that all Mineral Oils manufactured for use in hydraulic brakes (not the stuff you can buy from the local pharmacy or drug store) are compatible with each other, but our earlier thoughts were questioned after reading a very informative Q&A session conducted by the good folks at Bike Rumor recently. Since brake fluids’ boiling points are important, here is the collated boiling points of all the brake fluid types: Brake Fluid

It is worth noting that this type of fluid starts to boil at the lowest temperature of any type of brake fluid out there. More precisely the dry boiling point is at about 401 degrees Fahrenheit while the wet boiling point is at about 284 degrees Fahrenheit. As you can see all of the glycol- based DOT fluids (3, 4 & 5.1) are fully compatible with each other and can be readily mixed or swapped without adversely affecting the brake's performance or its characteristics. The main change will come in a decrease or increase in the boiling point of the brake fluid as a whole. In accordance with the specified criteria, DOT 4 has a boiling point of 230° Cdry and 155° C wet. Only use DOT 4 brakes if your braking system recommends them or if the automobile manufacturer has specifically instructed you to do so.Although DOT fluid lets in moisture, the water doesn’t pool in one place and is instead dispersed throughout the entirety of the fluid, which maintains good performance.