Can I Use DOT 5 Brake Fluid Or Stick To DOT 3 Or DOT 4 On Demco Brake Actuators?
Updated 08/15/2025 | Published 07/21/2025
Question:
Can I use this with DOT 5 brake fluid? thx, Lee
asked by: Lee
Expert Reply:
Good question Lee. Most people don't think about fluid compatibility, but it's important.
Demco actuators like the DA75 Trailer Brake Actuator - Zinc - Disc # DM33CV are technically compatible with DOT 5 fluid, but only when it's new. It CANNOT be mixed with other fluids since it's a silicone-based fluid.
It's best to stick with standard DOT 3 or DOT 4, both of which are compatible with the internal seals and materials and can be mixed together. These can be found at any auto parts store and most gas stations.
What trailer are you putting this on?
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Product Page this Question was Asked From
Demco DA75 Trailer Brake Actuator for Disc Brakes - Zinc Plated - 2" Ball - 7,500 lbs
- Brake Actuator
- Surge Brake Actuator
- Boat Trailer
- Travel Trailer
- Utility Trailer
- Bolt-On
- 7500 lbs GTW
- 2 Inch Ball Coupler
- 3 Inch Channel Tongue
- Disc Brakes
- Electric Lockout
- Demco
more information >
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Andrew N.
8/15/2025
Hey Lee, did you decide to go with DOT 3 or DOT 4 fluid for your trailer? I'm curious to know how it worked out for you since it helps me assist others in similar situations.