How To Activate Surge Brakes on Triple Axle To Verify Brakes Are All Working Properly
Question:
i own a heritage triple axel trailer with the demco surge brake system non electric. I want to check to insure all the brakes are activating. What is the best wat way to apply All the brake at the same time so i can try to spin the tires? The trailer is jacked up, with tires off the ground at this time thank you
asked by: Steve
Expert Reply:
There are 2 ways to activate a surge brake actuator. This is going to require you to have 2 people if you are wanting to then spin the tires to ensure the brakes are working correctly. I have linked a help article near the bottom of the page which goes into further detail and will help you visually see since there are images.
The first way involves using a flat head screwdriver to manually push the master cylinder rod and send pressure to the brakes. Not all actuators have the ability to do this so you will need to see if you can operate your Demco actuator this way.
If not the 2nd method involves using a scrap piece of lumber like a 2x4 along with the safety chains. You will hook the safety chains around the bottom of the 2x4 and push the top of the board against the coupler pressing it into the actuator. With the actuator pushed in then you will be able to check the brakes and make any necessary adjustments.
Depending on how old your brake fluid is you may want to flush and bleed your brakes prior to doing any adjustments. This may also help if you are having some of the brakes not locking up like the others. There could be some air that got inside the caliper preventing that wheel from locking up.

Product Page this Question was Asked From
Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs
- Accessories and Parts
- Trailer Brakes
- Hydraulic Drum Brakes
- RH
- 3500 lbs
- Brake Assembly
- Single Servo
- 10 x 2-1/4 Inch Drum
- Demco
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Q&A: Difference Between etrailer and Timken Bearing Kit
- Article: Trailer Drum Brakes vs. Disc Brakes: Making the Decision
- Q&A: Will The Demco Agricultural Trailer Brake Drum DM03532 Replace The Dexter T1885900?
- Q&A: Demco vs. etrailer Hydraulic Dacromet 3,500 lb Trailer Brakes
- Article: How to Adjust Your Trailer Brakes | The Ultimate Guide
- Q&A: How to Know When a Trailer Coupler Shock is Bad
- Q&A: Replacement Bearings, Seals, Hubs For 2021 Riverside Retro 135 With 3,500 lb Axle
- Q&A: How to Determine Correct Replacement Hydraulic Brake Actuator for Older Boat Trailer
- Q&A: How to Use the Lockout on the Titan Brake Actuator with Manual Lockout Part # T63FR
- Article: Most Popular Wheel Bearings
- Article: How to Bleed Your Trailer Surge Brakes
- Article: Boat Trailer Guides: Which are the Best?
Steve L.
4/3/2024
Thank you