Motul RBF 600 vs Motul RBF 660

Are you looking for reliable brake fluid for your vehicle? Then you should definitely take a look at the two top-notch brake fluids from Motul: RBF 600 and RBF 660. Both of these brake fluids are of great quality and provide superior performance and protection for your brakes.

Though both of these oils have a number of features in common; there are some key differences that you should be aware of before making your decision. In this article, we will make a comparison between Motul RBF 600 vs Motul RBF 660 so that you can determine which is better to choose.

So why late? Let’s dig into the article.

A Comparison between Motul RBF 600 VS Motul RBF 660

Motul RBF 600 and 660 are two of the most popular brake fluids in the market. Both brake fluids are synthetic, high-performance fluids designed for use in modern hydraulic brake and clutch systems. But which is better between these two fluids? Check out this comparison between Motul RBF 600 VS Motul RBF 660 and pick one that is suitable for your vehicle.

Temperature Range 

Motul RBF 600 has a temperature range of -40 to +300 degrees Fahrenheit, while Motul RBF 660 has a temperature range of -50 to +350 degrees Fahrenheit.

This means that Motul RBF 660 can withstand higher temperatures before it starts to break down. If you’re working in an environment where the temperatures routinely exceed 300 degrees Fahrenheit, then you’ll want to choose Motul RBF 660 so that your brake fluid doesn’t start to lose its effectiveness.

Boiling Point 

When it comes to comparing the boiling points of Motul RBF 600 and Motul RBF 660, there is a big difference. The boiling point of Motul RBF 600 is 315°C or 599°F, while the same for Motul RBF 660 is 350°C or 662°F.

It means that the higher boiling point provided by Motul RBF 660 offers an increased level of protection during high-performance applications and better thermal stability. It also helps in preventing the fluid from vaporizing too quickly, thus increasing its lifespan and reducing maintenance costs.

Compatibility of the Fluids

You may also want to consider the compatibility of the fluids when deciding between Motul RBF 600 and Motul RBF 660. Motul RBF 600 is compatible with both organic and inorganic acid-based brake fluids, while Motul RBF 660 is only compatible with organic acid-based brake fluids. That means that if you’re running a system that uses inorganic fluid, you won’t be able to use the latter.

If you’re not sure which type of fluid your system is using, it might be worth checking with the manufacturer before making a purchase. If you’re doing an entire brake rebuild or swap, make sure to check your vehicle specifications and make sure that the fluid you choose is correct for your specific model. That way, you don’t have to worry about any surprises later on down the road.


The viscosity of a fluid is almost as important of a factor as its boiling point. Viscosity is essentially a measurement of how liquid the brake fluid is compared to regular oil. The thicker the fluid, the more resistant it is to temperature changes, but this can also make it less effective at transferring heat.

The Motul RBF 660 has a higher viscosity than the Motul RBF 600, which means that it is thicker and less likely to be affected by temperature variations. However, this does make it slightly less effective at transferring heat away from the brakes.

Considering that both fluids are engineered for high-performance vehicles, the difference in viscosity may be negligible for most drivers.

Ultimately, you should choose the fluid that best suits your needs—if you’re looking for maximum protection and longer-lasting performance in extreme temperatures, then go with the Motul RBF 660; if you’re looking for more balanced protection and performance without sacrificing too much in terms of boiling point, then go with the Motul RBF 600.

Fluid Replacement Interval 

The next key point of discussion lies in the fluid replacement interval between Motul RBF 600 and Motul RBF 660. With normal city driving and off-roading, Motul RBF 600 is recommended to be replaced every 24 months or 20,000 kilometers.

On the other hand, Motul RBF 660 is recommended to be replaced every 12 months or 10,000 kilometers. To sum up, based on the usage and location of your vehicle, you should definitely decide which one is more suitable for your brakes.

Corrosion Protection 

When it comes to corrosion protection, both the Motul RBF 600 and Motul RBF 660 are excellent choices. Both fluids are formulated with special corrosion inhibitors to prevent rust and corrosion within the braking system.

The RBF 600 is slightly more protective, as it is designed to protect up to 402 degrees Fahrenheit. The 660 is designed for temperatures up to 572 degrees Fahrenheit, so you may want to opt for this option if you require more heat protection. However, both fluids should offer plenty of performance under normal driving conditions.


Now you might be wondering about the cost. Both Motul RBF 600 and RBF 660 come in 1-liter bottles and cost about the same, between US$12-15. So it’s mostly a matter of preference when it comes to choosing one over the other.

If you’re into DIY car maintenance and care, consider investing in both fluids. Then when temperatures dip or rise above the stated limits for either fluid, you have a backup ready to go.

It’s important to take into account all the factors for both Motul RBF 600 and 660 before making a decision on which fluid is right for your vehicle. Keep in mind that both are great options, but you should also be aware of their respective limits and how they can impact your car’s performance level.

Motul RBF 600 vs Motul RBF 660 – The Winner

When it comes to selecting the right brake fluid for your vehicle, the Motul RBF 600 and the Motul RBF 660 are two of the most popular choices. Both are high-performance brake fluids that deliver excellent stopping power and durability. But you just need to pick the better one between Motul RBF 600 vs Motul RBF 660.

It is very difficult to pick the suitable one between these two fluids. Ultimately, if you’re looking for a brake fluid that can handle high temperatures, go with Motul RBF 600. However, if you want more compatibility or precision in your brake system, then Motul RBF 660 could be the better choice for you.

Frequently Asked Questions

Can you mix RBF 600 and 660?

They are both DOT-4 fluids, and from the same manufacturer, so they should be safe to mix. Obviously to get the full benefit of the 660’s higher dry boiling temp’ you should do a full flush and bleed.

What is DOT 3 brake fluid?

DOT 3 brake fluid is a polyethylene glycol-based fluid that has been designed to withstand very cold temperatures without thickening and to endure high temperatures without boiling. The typical boiling temperature of DOT 3 brake fluid is around 250° C.

How often do you change the brake fluid in Motul?

It is recommended to change your brake fluid every two years or 24,000 miles, whichever comes first.

Final Thought

When it comes to choosing between Motul RBF 600 vs Motul RBF 660, it can be tough to decide which is the best option. Both of these fluids are great for high-performance cars, but they do have some key differences.

In this article, we try to make a comparison between these two fluids so that you can make a decision which is better to choose. Hopefully, this small effort will be helpful for all of you. Thank you all.


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