Electric Brake Maintenance: How to Properly Adjust Your Trailer Brakes
Trailer Parts Unlimited | Jul 13th 2022
Maintaining your trailer's electric brakes is critical for safe towing. Whether you’re hauling a car hauler, flatbed, or equipment trailer, making sure your brake shoes are adjusted correctly can prevent uneven wear, overheating, and dangerous braking performance.
When to Adjust Trailer Electric Brakes
- Initial Adjustment: 250–300 miles after new brake components have been installed
- Routine Maintenance: At least every 3,000 miles depending on terrain, load weight, and towing frequency
Tip: If your trailer feels like it's pulling unevenly or brakes are getting hot, check adjustment immediately.
⚠️ Safety First: Jacking Up Your Trailer
Before beginning any work:
- ❌ Do NOT place a jack directly under your axle or springs
- ✅ Use proper frame support and jack stands to keep the trailer secure
Always follow your trailer manufacturer’s recommendations for jacking points and lifting procedure.
Step-by-Step: How to Adjust Electric Trailer Brakes
- Park Safely & Prepare the Area
Make sure your trailer is parked on a level surface and chocked properly. Clear the area of any tools or trip hazards. - Lift the Trailer & Support It
Use a hydraulic jack and secure the trailer with jack stands placed under the frame, not the axle. Ensure the wheel is off the ground and can rotate freely. - Locate the Adjustment Hole
On the brake backing plate (behind the wheel), find the rubber adjusting plug and remove it to access the star wheel. - Expand the Brake Shoes
Using a brake spoon or flat adjuster tool, turn the star wheel until the wheel becomes hard to turn by hand (the brake shoes are now expanded). - Back Off Slightly
Slowly turn the star wheel in the opposite direction just enough so you feel a slight drag or resistance when turning the wheel by hand. - Replace the Plug
Put the rubber adjusting hole cover back on the backing plate. - Lower the Trailer
Carefully remove the jack stands and lower the tire back to the ground. - Repeat for All Wheels
Adjust each brake on all axles individually — don't skip any wheels. Even adjustment ensures consistent braking across the trailer.
Important Notes
- Adjusting brakes incorrectly can lead to premature wear or brake lock-up
- This process is for self-adjusting and manual electric brake assemblies
- Carter, Dexter, and most major trailer brake brands follow this procedure
Staff & Customer Training Tips
- ✅ Always inspect brakes after a long trip or when loading heavy
- ✅ Check for dust buildup or grease contamination while adjusting
- ✅ Keep a brake spoon and work gloves in your trailer toolbox