Trailer brake adjustment is often overlooked, especially by inexperienced drivers, which compromises safety. Properly adjusted brakes not only increase towing safety but also extend the life of your trailer’s braking system, reducing premature failures and replacement costs.
In this guide post, you will learn the step-by-step process of adjusting trailer brakes, so you can easily adjust your trailer brakes and reduce safety risks on the road.
How Do Electric Trailer Brakes Work?
Electric trailer brakes operate through a brake controller in the towing vehicle. When the driver applies the brakes, the controller sends an electrical signal to the trailer’s brake magnets. These magnets create a magnetic field, pulling the brake shoes against the drum to generate friction and slow the wheels.
When the driver releases the brake pedal, the signal is cut off, disengaging the magnets and allowing the wheels to rotate freely. Regular adjustments are essential to maintain optimal braking performance and ensure safe towing.
How To Adjust Trailer Disc and Drum Brakes?
To adjust trailer brakes 1. Gather appropriate equipment. 2. Jack up the trailer. 3. Locate the brake adjustment mechanism. 4. Remove the brake adjustment cover. 5. Rotate the brake star wheel. 6. Spin the trailer wheel. 7. Repeat this process for all wheels. 8. Test trailer brakes.
Most trailers use electric brakes. These brakes are operated through the towing vehicle’s brake controller. Therefore, before adjusting trailer brakes, it is important to know the procedure and the proper tools to use so that you can adjust them easily and safely.
#1. Gather the Appropriate Tools
You will need the following tools to adjust trailer brakes:
- Jack stands
- Adjustable wrench
- Flathead screwdriver
- Brake spoons
- Socket wrench
- Wheel chocks
#2. Jack Up The Trailer
Securely jack up the trailer before adjusting the trailer brakes, and make sure the trailer jack stands are securely in place and the trailer is stable and will not move during the adjustment process. Since moving the trailer during adjustment can be a safety hazard, the brake adjustment will not be accurate.
#3. Locate The Trailer Adjustment Mechanism
Next, you should identify what type of brake system is installed on your trailer. Most trailers have the brake adjustment mechanism located on the brake assembly itself, in which case you may find an access port on the brake backing plate that will allow you to reach the adjustment mechanism.
#4. Adjusting Trailer Drum Brakes
- Remove the brake adjustment cover: Remove the rubber plug or access port cover on the brake drum backing plate, so you can make the necessary adjustments by turning the star wheel.
- Turn the brake star wheel: Next, using a brake adjustment tool or screwdriver, turn the adjustment star wheel to extend or retract the brake shoes. Also, apply a slight pull on the drum to ensure your trailer wheel is not stuck.
- Turn the trailer wheel: Now turn the trailer wheel and adjust the brake until you feel a slight pull. When you feel a slight pull on the wheel, pull the brake adjustment star wheel back slightly.
- Repeat this process for all wheels: To ensure consistent adjustment, repeat this process for all wheels on the trailer. Turn the trailer wheel slowly when making brake adjustments, as brakes that are too tight can completely damage your trailer’s brake system and put extra load on the towing vehicle.
#5. Adjusting Trailer Hydraulic Disc Brakes
You should always keep in mind that the adjustment process for disc brakes is different from that for drum brakes.
- Find the brake adjustment location: Locate the adjustment nut or bolt on the trailer brake caliper assembly, which will allow you to adjust the brakes.
- Use the wrench: Use the wrench to turn the adjustment nut or bolt to tighten the brake pads onto the rotor.
- Turn the adjustment bolt/nut: Turn the trailer wheel and adjust it until you feel a slight pull. When you feel a slight pull while turning the trailer wheel, back off the brake adjustment bolt or nut slightly.
- Repeat the process: Repeat this process for all wheels to maintain uniform braking on all wheels.
- Check the brake fluid level: Check the brake fluid level after performing the hydraulic disc brake adjustment. If the brake fluid level is low, fill it up. Because hydraulic disc brakes work based on fluid.
#6. Test The Brakes
After adjusting the trailer brakes, remove the trailer from the jack stands and give it a test drive. Also, make sure the brakes are applied smoothly and evenly. If you notice any unusual sounds, adjust them to the correct point.
Why Is Trailer Brake Adjustment Necessary?
Trailer brake adjustment is essential to ensuring safe towing of any trailer, so properly adjusted brakes optimize trailer stopping power and prevent excessive wear and overheating of the brake system. A well-adjusted brake system reduces the risk of accidents and promotes overall road safety.
If you regularly adjust the brakes on your trailer, it will maintain brake efficiency, which will reduce wear and tear on the brake pads.
Neglecting trailer brake adjustment may result in inadequate braking performance and compromise the stability of the towing vehicle and trailer combination, creating a potentially dangerous situation on the road.
What Should Be Kept in Mind When Adjusting Trailer Brakes?
- When adjusting trailer brakes, apply equal braking force to all wheels.
- Always lock the trailer wheels and release the trailer parking brake when adjusting the brakes.
- Spin the wheels by hand to identify any resistance or drag when adjusting the brakes.
- Adjust the brake shoes on all wheels evenly.
- Inspect brake components for wear as part of routine maintenance. trailer
- Always prioritize safety, as properly adjusted trailer brakes are essential for stable and safe towing.
- Proper brake adjustment helps prevent issues such as uneven tire wear on the trailer, low braking efficiency, and potential accidents on the road.
Common Mistakes to Avoid When Adjusting Trailer Brakes
Here are some common mistakes to avoid when adjusting trailer brakes:
#1. Over-Tightening the Brakes
- Over-adjusting the brake shoes or pads can cause excessive drag, leading to overheating and premature wear. Always adjust until you feel slight resistance, then back off slightly.
#2. Not Checking the Brake Type
- Drum and disc brakes have different adjustment methods. Using the wrong process can result in improper braking performance.
#3. Skipping Wheel Chocks and Jack Stands
- Failing to secure the trailer properly can cause it to move during adjustment, creating a serious safety hazard. Always use wheel chocks and jack stands.
#4. Ignoring Brake Fluid Levels (For Hydraulic Brakes)
- Low brake fluid can cause poor braking performance or brake failure. Always check and refill the fluid after making adjustments.
#5. Not Testing the Brakes After Adjustment
- Skipping a test drive can lead to undetected issues like uneven braking or excessive resistance. Always test the brakes under controlled conditions before towing.
By avoiding these mistakes, you can ensure your trailer brakes are adjusted correctly for safe and smooth operation.
Conclusion
Proper trailer brake adjustment ensures safe towing and smooth performance. Avoid common mistakes like over-tightening, skipping safety steps, and neglecting brake fluid.
Always test your brakes after adjustment for reliability. Regular maintenance keeps your braking system efficient and extends its lifespan.
For more expert tips on trailer maintenance and repair, stay tuned to Auto Repair Zone!
Banty Paul, owner and founder of Auto Repair Zone, brings over 14 years of hands-on experience in automotive repair and maintenance. This blog was created to share expert troubleshooting guides, repair tips, maintenance advice, and cost estimates for cars and semi-trucks.
