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?
(click to enlarge)
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 >
Continue Researching
- Q&A: Reverse Lockout Solenoid For Dexter DX12.5 Actuator
- Q&A: Demco DA75 Disc Brake Actuator For Tandem Trailer With Kodiak Disc Brakes
- Q&A: Can I Run Velit 12V Air Conditioner In My Camper Van While Driving?
- Q&A: Looking For A Replacement Actuator For My Titan 10 Surg-O-Matic
- Q&A: Replacement for a Tie Down 70lc Brake Actuator
- Q&A: Replacement Brake Actuator For 1995 ShoreLander Trailer With Drum Brakes
- Q&A: Brake Lines for Boat Trailer In Salt Water
- Article: Trailer Lighting Requirements
- Article: How to Bleed Your Trailer Surge Brakes
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.