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What kind of brake fluid does an Acura take?

Acura vehicles generally require glycol-based brake fluids—DOT 3, DOT 4, or DOT 5.1—depending on the model and year. The exact grade is specified in the owner’s manual or on the reservoir cap, so verify your specific vehicle’s specification before replacing fluid.

Understanding brake fluid grades and Acura compatibility

Brake fluid is categorized by DOT grade, which reflects its boiling point, moisture tolerance, and compatibility with the braking system. Acura’s newer and higher-performance models typically use higher-grade fluids (DOT 4 or DOT 5.1) to cope with heat and heavy braking, but many older or base models still rely on DOT 3. Silicone-based DOT 5 is uncommon in Acura systems and is not compatible with glycol-based fluids. Always match the grade to the manufacturer’s specification to ensure proper ABS function and braking performance.

DOT grade basics

DOT 3, DOT 4, and DOT 5.1 are glycol-based fluids with increasing boiling points and moisture tolerance. DOT 5 is silicone-based and generally not compatible with standard Acura braking systems. Do not mix DOT grades in the same system and avoid switching from a higher to a lower grade without a complete brake-system flush and proper confirmation from a technician.

To determine the exact grade for your vehicle, consider these steps:

Check the owner’s manual for the official DOT grade specified for your model and year.

Inspect the brake fluid reservoir cap or nearby labeling for DOT grade indications (e.g., DOT 3, DOT 4, or DOT 5.1).

If the labeling is unclear, contact an Acura dealer or a qualified mechanic to confirm the correct grade.

Do not mix different DOT grades within the same braking system.

If upgrading to a higher-grade fluid (for better heat resistance), ensure the system is fully compatible and consider a professional flush.

Bottom line: in most modern Acuras, DOT 4 is the common standard, with DOT 5.1 used in some high-temperature or performance-oriented applications; always verify the exact requirement for your vehicle. Regularly replacing brake fluid (typically every 2–3 years, or as advised by the manual) helps prevent moisture buildup and maintains braking effectiveness.

What to know for newer vs older Acura models

On many contemporary Acura models, DOT 4 is the standard choice due to its higher boiling point and better resistance to heat. DOT 5.1 is used in certain high-performance situations where the system is designed to handle it. Older Acura models or entry-level trims may specify DOT 3. It is essential to confirm the grade from the vehicle’s documentation rather than assuming.

Most newer Acura models specify DOT 4 as the baseline fluid, with DOT 5.1 available where high-heat performance is required and the system supports it.

DOT 3 remains common on older models or specific configurations, but always verify with the manual.

DOT 5 (silicone-based) is not typically used in Acura braking systems and should not be mixed with glycol-based fluids.

If you are changing fluid grade (for example, from DOT 3 to DOT 4 or DOT 5.1), plan for a complete system flush to avoid compatibility issues.

When in doubt, consult an Acura service advisor or licensed mechanic to confirm the correct grade for your particular vehicle.

In practice, sticking to the official specification is the safest approach. Using the wrong grade can reduce braking performance, impair ABS function, or cause internal damage over time. A dealer or service center can verify the correct fluid for your exact model and year, especially if you’re considering a higher-grade fluid for performance reasons.

Summary

Brake fluid for Acura vehicles is not universal. Always confirm the exact DOT grade (3, 4, or 5.1) specified for your model in the owner’s manual or on the reservoir label. Do not use DOT 5 silicone-based fluid in a glycol-based system, and perform a full system flush when changing grades. Regular maintenance, typically every 2–3 years, helps maintain braking performance and safety. If you’re unsure, consult a trusted Acura dealer or qualified mechanic for guidance tailored to your car.

What happens if I put DOT 3 instead of dot 4?

If you put DOT 3 brake fluid in a system that requires DOT 4, the main risk is reduced braking performance in high-heat situations because DOT 3 has a lower boiling point. While the fluids are compatible and mixing them is acceptable in a pinch, it's best to use the manufacturer-recommended fluid to ensure maximum brake safety, especially for high-performance or heavy-duty applications.
What happens

Lower boiling point: DOT 3 has a lower boiling point (205∘C205 raised to the composed with power cap C205∘𝐶 dry, 140∘C140 raised to the composed with power cap C140∘𝐶 wet) compared to DOT 4 (230∘C230 raised to the composed with power cap C230∘𝐶 dry, 155∘C155 raised to the composed with power cap C155∘𝐶 wet).
Potential for brake fade: In situations like descending a long, steep hill or aggressive driving, the brake fluid can get hot enough to boil. DOT 3 is more likely to reach its boiling point than DOT 4, which can cause a spongy brake pedal and loss of braking power (brake fade).
Incompatibility with DOT 5: DOT 3 is not compatible with silicone-based DOT 5 fluid. Never mix DOT 3, 4, or 5.1 with DOT 5 fluid, as this can damage the brake system.

What to do

Use the correct fluid: Always use the specific type of brake fluid recommended by your vehicle's manufacturer for safety and optimal performance.
If you mixed them: If you've accidentally mixed the two, it's not an immediate emergency for normal driving, but it's recommended to have the system flushed and refilled with the correct DOT 4 fluid. This will ensure you have the higher temperature safety margin that was originally specified for your car.
Wipe up spills: Brake fluid can damage paint. Be sure to wipe up any spills immediately.

Do I want DOT 3 or dot 4 brake fluid?

You should use DOT 3 or DOT 4 brake fluid based on your vehicle's manufacturer specifications, which can be found in your owner's manual. If your car requires DOT 3, you can upgrade to DOT 4 for its higher boiling point, which is beneficial for high-temperature braking or frequent use, but do not use DOT 3 if your car calls for DOT 4.
When to use DOT 3

Daily driving: Most standard cars and trucks use DOT 3 for moderate braking conditions.
If specified: Always use DOT 3 if it is the fluid specified by your vehicle's manufacturer.

When to use DOT 4

For higher performance: DOT 4 has higher boiling points, making it better for high-performance vehicles or situations where brakes are used frequently, like in hilly terrain or towing.
If specified: Some modern vehicles, especially those with ABS systems, may specifically require DOT 4.
Upgrading from DOT 3: If your car currently uses DOT 3, you can upgrade to DOT 4 for improved performance and a higher safety margin. The two are compatible and can be mixed, though it's generally recommended to use the higher-spec fluid if you have the option.

Key differences

Boiling points: DOT 4 has higher dry and wet boiling points than DOT 3, meaning it can withstand higher temperatures before it begins to boil and lose effectiveness.
Moisture absorption: Both fluids are hygroscopic, meaning they absorb moisture over time, which lowers their boiling point. Because DOT 4 has a higher starting boiling point, it has more of a buffer before becoming a safety risk.

Important considerations

Check your manual: Always refer to your car's owner's manual for the correct brake fluid specification to ensure compatibility and prevent system damage.
Do not use lower-spec fluid: Never use a lower-spec fluid (like DOT 3) in a vehicle that requires a higher-spec fluid (like DOT 4).
Do not mix DOT 3 and DOT 5: While DOT 3 and DOT 4 are compatible, DOT 5 is silicone-based and should not be mixed with either glycol-based DOT 3 or DOT 4 fluids.

Is it okay to mix DOT 3 and dot 4 brake fluid?

Yes, you can mix DOT 3 and DOT 4 brake fluid, as they are chemically compatible, but you should never mix them with DOT 5. Mixing DOT 3 and DOT 4 is acceptable because both are glycol-based. Adding DOT 4 to DOT 3 will lower its boiling point, while adding DOT 3 to DOT 4 will lower its boiling point.
This video explains the differences between DOT 3 and DOT 4 brake fluid and whether they can be mixed: 1mHVAC Mechanic YouTube · Dec 28, 2021
Compatibility and mixing

DOT 3 and DOT 4: These are compatible and can be mixed without causing harm to the braking system.
DOT 3, 4, and 5.1: These are all compatible with each other and can be mixed.
DOT 5: This is silicone-based and is not compatible with DOT 3, DOT 4, or DOT 5.1. Mixing them will cause the system to fail.

What to consider when mixing

Boiling point: DOT 4 has a higher boiling point than DOT 3. Mixing them will lower the overall boiling point of the fluid in your system.
Performance: If your car requires DOT 4 and you mix it with DOT 3, you will reduce the braking system's performance.
Best practice: It is best to check your vehicle's manual and use the specific DOT fluid recommended for your car. If you need to upgrade to DOT 4, it is best to completely flush the old DOT 3 fluid out first to get the full benefits of the DOT 4 fluid.

This video explains what happens when you mix DOT 3 and DOT 4 brake fluids: 50sMotor MatchupsYouTube · Jan 2, 2024

What brake fluid does Acura use?

Dot 3
Genuine Honda And Acura Brake Fluid Dot 3 (Pack Of 2)

Kevin Bennett

Company Owner

Kevin Bennet is the founder and owner of Kevin's Autos, a leading automotive service provider in Australia. With a deep commitment to customer satisfaction and years of industry expertise, Kevin uses his blog to answer the most common questions posed by his customers. From maintenance tips to troubleshooting advice, Kevin's articles are designed to empower drivers with the knowledge they need to keep their vehicles running smoothly and safely.