How to Tell if 3,500 lb Hydraulic Drum Brakes Have Free Backing Feature
Updated 01/27/2026 | Published 08/24/2024
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Question:
i have a trailer with 3500 pond axles. im not sure if they are backing or non backing drum brakes, is there a way to tell ?
asked by: Dustin J
0
Expert Reply:
Hey Dustin, thanks for reaching out!
The only surefire way to know if your brakes are free backing or not is to hook your trailer up to your vehicle and back up. If your trailer tires lock up then you have standard hydraulic brakes and need the kit # AKUBRK-35, but if the trailer tires back up without locking up then you have free backing and need the kit # AKFBBRK-35.
expert reply by:
Jon G
0
Product Page this Question was Asked From
etrailer Hydraulic Trailer Brakes - Uni-Servo - 10" - Left/Right - 3.5K
- Trailer Brakes
- Hydraulic Drum Brakes
- Standard Grade
- Manual Adjust
- Single Servo
- 10 x 2-1/4 Inch Drum
- 3500 lbs Axle
- 14 Inch Wheel
- 14-1/2 Inch Wheel
- 15 Inch Wheel
- etrailer
more information >
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Robin H.
1/27/2026
Hey Dustin, how did your test go when you backed up the trailer to check the brakes? Knowing which type you have could really help others trying to tell the difference on their own setups.